3014 lines
91 KiB
C
3014 lines
91 KiB
C
/*-------------------------------------------------------------------------
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*
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* analyze.c
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* transform the raw parse tree into a query tree
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*
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* For optimizable statements, we are careful to obtain a suitable lock on
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* each referenced table, and other modules of the backend preserve or
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* re-obtain these locks before depending on the results. It is therefore
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* okay to do significant semantic analysis of these statements. For
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* utility commands, no locks are obtained here (and if they were, we could
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* not be sure we'd still have them at execution). Hence the general rule
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* for utility commands is to just dump them into a Query node untransformed.
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* DECLARE CURSOR, EXPLAIN, and CREATE TABLE AS are exceptions because they
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* contain optimizable statements, which we should transform.
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*
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*
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* Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* src/backend/parser/analyze.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "access/sysattr.h"
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#include "catalog/pg_type.h"
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#include "miscadmin.h"
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#include "nodes/makefuncs.h"
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#include "nodes/nodeFuncs.h"
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#include "optimizer/optimizer.h"
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#include "parser/analyze.h"
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#include "parser/parse_agg.h"
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#include "parser/parse_clause.h"
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#include "parser/parse_coerce.h"
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#include "parser/parse_collate.h"
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#include "parser/parse_cte.h"
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#include "parser/parse_expr.h"
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#include "parser/parse_func.h"
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#include "parser/parse_oper.h"
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#include "parser/parse_param.h"
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#include "parser/parse_relation.h"
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#include "parser/parse_target.h"
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#include "parser/parsetree.h"
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#include "rewrite/rewriteManip.h"
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#include "utils/rel.h"
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/* Hook for plugins to get control at end of parse analysis */
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post_parse_analyze_hook_type post_parse_analyze_hook = NULL;
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static Query *transformOptionalSelectInto(ParseState *pstate, Node *parseTree);
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static Query *transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt);
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static Query *transformInsertStmt(ParseState *pstate, InsertStmt *stmt);
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static List *transformInsertRow(ParseState *pstate, List *exprlist,
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List *stmtcols, List *icolumns, List *attrnos,
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bool strip_indirection);
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static OnConflictExpr *transformOnConflictClause(ParseState *pstate,
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OnConflictClause *onConflictClause);
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static int count_rowexpr_columns(ParseState *pstate, Node *expr);
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static Query *transformSelectStmt(ParseState *pstate, SelectStmt *stmt);
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static Query *transformValuesClause(ParseState *pstate, SelectStmt *stmt);
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static Query *transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt);
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static Node *transformSetOperationTree(ParseState *pstate, SelectStmt *stmt,
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bool isTopLevel, List **targetlist);
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static void determineRecursiveColTypes(ParseState *pstate,
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Node *larg, List *nrtargetlist);
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static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt);
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static List *transformReturningList(ParseState *pstate, List *returningList);
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static List *transformUpdateTargetList(ParseState *pstate,
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List *targetList);
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static Query *transformDeclareCursorStmt(ParseState *pstate,
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DeclareCursorStmt *stmt);
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static Query *transformExplainStmt(ParseState *pstate,
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ExplainStmt *stmt);
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static Query *transformCreateTableAsStmt(ParseState *pstate,
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CreateTableAsStmt *stmt);
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static Query *transformCallStmt(ParseState *pstate,
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CallStmt *stmt);
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static void transformLockingClause(ParseState *pstate, Query *qry,
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LockingClause *lc, bool pushedDown);
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#ifdef RAW_EXPRESSION_COVERAGE_TEST
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static bool test_raw_expression_coverage(Node *node, void *context);
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#endif
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/*
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* parse_analyze
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* Analyze a raw parse tree and transform it to Query form.
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*
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* Optionally, information about $n parameter types can be supplied.
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* References to $n indexes not defined by paramTypes[] are disallowed.
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*
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* The result is a Query node. Optimizable statements require considerable
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* transformation, while utility-type statements are simply hung off
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* a dummy CMD_UTILITY Query node.
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*/
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Query *
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parse_analyze(RawStmt *parseTree, const char *sourceText,
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Oid *paramTypes, int numParams,
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QueryEnvironment *queryEnv)
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{
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ParseState *pstate = make_parsestate(NULL);
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Query *query;
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Assert(sourceText != NULL); /* required as of 8.4 */
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pstate->p_sourcetext = sourceText;
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if (numParams > 0)
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parse_fixed_parameters(pstate, paramTypes, numParams);
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pstate->p_queryEnv = queryEnv;
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query = transformTopLevelStmt(pstate, parseTree);
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if (post_parse_analyze_hook)
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(*post_parse_analyze_hook) (pstate, query);
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free_parsestate(pstate);
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return query;
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}
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/*
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* parse_analyze_varparams
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*
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* This variant is used when it's okay to deduce information about $n
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* symbol datatypes from context. The passed-in paramTypes[] array can
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* be modified or enlarged (via repalloc).
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*/
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Query *
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parse_analyze_varparams(RawStmt *parseTree, const char *sourceText,
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Oid **paramTypes, int *numParams)
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{
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ParseState *pstate = make_parsestate(NULL);
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Query *query;
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Assert(sourceText != NULL); /* required as of 8.4 */
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pstate->p_sourcetext = sourceText;
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parse_variable_parameters(pstate, paramTypes, numParams);
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query = transformTopLevelStmt(pstate, parseTree);
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/* make sure all is well with parameter types */
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check_variable_parameters(pstate, query);
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if (post_parse_analyze_hook)
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(*post_parse_analyze_hook) (pstate, query);
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free_parsestate(pstate);
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return query;
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}
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/*
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* parse_sub_analyze
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* Entry point for recursively analyzing a sub-statement.
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*/
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Query *
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parse_sub_analyze(Node *parseTree, ParseState *parentParseState,
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CommonTableExpr *parentCTE,
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bool locked_from_parent,
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bool resolve_unknowns)
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{
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ParseState *pstate = make_parsestate(parentParseState);
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Query *query;
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pstate->p_parent_cte = parentCTE;
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pstate->p_locked_from_parent = locked_from_parent;
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pstate->p_resolve_unknowns = resolve_unknowns;
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query = transformStmt(pstate, parseTree);
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free_parsestate(pstate);
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return query;
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}
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/*
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* transformTopLevelStmt -
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* transform a Parse tree into a Query tree.
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*
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* This function is just responsible for transferring statement location data
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* from the RawStmt into the finished Query.
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*/
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Query *
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transformTopLevelStmt(ParseState *pstate, RawStmt *parseTree)
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{
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Query *result;
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/* We're at top level, so allow SELECT INTO */
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result = transformOptionalSelectInto(pstate, parseTree->stmt);
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result->stmt_location = parseTree->stmt_location;
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result->stmt_len = parseTree->stmt_len;
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return result;
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}
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/*
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* transformOptionalSelectInto -
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* If SELECT has INTO, convert it to CREATE TABLE AS.
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*
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* The only thing we do here that we don't do in transformStmt() is to
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* convert SELECT ... INTO into CREATE TABLE AS. Since utility statements
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* aren't allowed within larger statements, this is only allowed at the top
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* of the parse tree, and so we only try it before entering the recursive
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* transformStmt() processing.
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*/
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static Query *
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transformOptionalSelectInto(ParseState *pstate, Node *parseTree)
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{
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if (IsA(parseTree, SelectStmt))
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{
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SelectStmt *stmt = (SelectStmt *) parseTree;
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/* If it's a set-operation tree, drill down to leftmost SelectStmt */
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while (stmt && stmt->op != SETOP_NONE)
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stmt = stmt->larg;
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Assert(stmt && IsA(stmt, SelectStmt) && stmt->larg == NULL);
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if (stmt->intoClause)
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{
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CreateTableAsStmt *ctas = makeNode(CreateTableAsStmt);
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ctas->query = parseTree;
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ctas->into = stmt->intoClause;
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ctas->objtype = OBJECT_TABLE;
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ctas->is_select_into = true;
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/*
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* Remove the intoClause from the SelectStmt. This makes it safe
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* for transformSelectStmt to complain if it finds intoClause set
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* (implying that the INTO appeared in a disallowed place).
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*/
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stmt->intoClause = NULL;
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parseTree = (Node *) ctas;
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}
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}
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return transformStmt(pstate, parseTree);
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}
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/*
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* transformStmt -
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* recursively transform a Parse tree into a Query tree.
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*/
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Query *
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transformStmt(ParseState *pstate, Node *parseTree)
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{
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Query *result;
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/*
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* We apply RAW_EXPRESSION_COVERAGE_TEST testing to basic DML statements;
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* we can't just run it on everything because raw_expression_tree_walker()
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* doesn't claim to handle utility statements.
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*/
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#ifdef RAW_EXPRESSION_COVERAGE_TEST
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switch (nodeTag(parseTree))
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{
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case T_SelectStmt:
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case T_InsertStmt:
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case T_UpdateStmt:
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case T_DeleteStmt:
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(void) test_raw_expression_coverage(parseTree, NULL);
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break;
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default:
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break;
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}
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#endif /* RAW_EXPRESSION_COVERAGE_TEST */
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switch (nodeTag(parseTree))
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{
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/*
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* Optimizable statements
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*/
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case T_InsertStmt:
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result = transformInsertStmt(pstate, (InsertStmt *) parseTree);
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break;
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case T_DeleteStmt:
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result = transformDeleteStmt(pstate, (DeleteStmt *) parseTree);
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break;
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case T_UpdateStmt:
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result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree);
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break;
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case T_SelectStmt:
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{
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SelectStmt *n = (SelectStmt *) parseTree;
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if (n->valuesLists)
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result = transformValuesClause(pstate, n);
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else if (n->op == SETOP_NONE)
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result = transformSelectStmt(pstate, n);
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else
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result = transformSetOperationStmt(pstate, n);
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}
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break;
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/*
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* Special cases
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*/
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case T_DeclareCursorStmt:
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result = transformDeclareCursorStmt(pstate,
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(DeclareCursorStmt *) parseTree);
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break;
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case T_ExplainStmt:
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result = transformExplainStmt(pstate,
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(ExplainStmt *) parseTree);
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break;
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case T_CreateTableAsStmt:
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result = transformCreateTableAsStmt(pstate,
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(CreateTableAsStmt *) parseTree);
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break;
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case T_CallStmt:
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result = transformCallStmt(pstate,
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(CallStmt *) parseTree);
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break;
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default:
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/*
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* other statements don't require any transformation; just return
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* the original parsetree with a Query node plastered on top.
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*/
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result = makeNode(Query);
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result->commandType = CMD_UTILITY;
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result->utilityStmt = (Node *) parseTree;
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break;
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}
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/* Mark as original query until we learn differently */
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result->querySource = QSRC_ORIGINAL;
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result->canSetTag = true;
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return result;
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}
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/*
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* analyze_requires_snapshot
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* Returns true if a snapshot must be set before doing parse analysis
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* on the given raw parse tree.
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*
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* Classification here should match transformStmt().
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*/
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bool
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analyze_requires_snapshot(RawStmt *parseTree)
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{
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bool result;
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switch (nodeTag(parseTree->stmt))
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{
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/*
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* Optimizable statements
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*/
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case T_InsertStmt:
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case T_DeleteStmt:
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case T_UpdateStmt:
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case T_SelectStmt:
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result = true;
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break;
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/*
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* Special cases
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*/
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case T_DeclareCursorStmt:
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case T_ExplainStmt:
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case T_CreateTableAsStmt:
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/* yes, because we must analyze the contained statement */
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result = true;
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break;
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default:
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/* other utility statements don't have any real parse analysis */
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result = false;
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break;
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}
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return result;
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}
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/*
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* transformDeleteStmt -
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* transforms a Delete Statement
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*/
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static Query *
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transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt)
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{
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Query *qry = makeNode(Query);
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ParseNamespaceItem *nsitem;
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Node *qual;
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qry->commandType = CMD_DELETE;
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/* process the WITH clause independently of all else */
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if (stmt->withClause)
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{
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qry->hasRecursive = stmt->withClause->recursive;
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qry->cteList = transformWithClause(pstate, stmt->withClause);
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qry->hasModifyingCTE = pstate->p_hasModifyingCTE;
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}
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/* set up range table with just the result rel */
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qry->resultRelation = setTargetTable(pstate, stmt->relation,
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stmt->relation->inh,
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true,
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ACL_DELETE);
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nsitem = pstate->p_target_nsitem;
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/* there's no DISTINCT in DELETE */
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qry->distinctClause = NIL;
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/* subqueries in USING cannot access the result relation */
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nsitem->p_lateral_only = true;
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nsitem->p_lateral_ok = false;
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/*
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* The USING clause is non-standard SQL syntax, and is equivalent in
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* functionality to the FROM list that can be specified for UPDATE. The
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* USING keyword is used rather than FROM because FROM is already a
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* keyword in the DELETE syntax.
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*/
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transformFromClause(pstate, stmt->usingClause);
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/* remaining clauses can reference the result relation normally */
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nsitem->p_lateral_only = false;
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nsitem->p_lateral_ok = true;
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qual = transformWhereClause(pstate, stmt->whereClause,
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EXPR_KIND_WHERE, "WHERE");
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qry->returningList = transformReturningList(pstate, stmt->returningList);
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/* done building the range table and jointree */
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qry->rtable = pstate->p_rtable;
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qry->jointree = makeFromExpr(pstate->p_joinlist, qual);
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qry->hasSubLinks = pstate->p_hasSubLinks;
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qry->hasWindowFuncs = pstate->p_hasWindowFuncs;
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qry->hasTargetSRFs = pstate->p_hasTargetSRFs;
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qry->hasAggs = pstate->p_hasAggs;
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assign_query_collations(pstate, qry);
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/* this must be done after collations, for reliable comparison of exprs */
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if (pstate->p_hasAggs)
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parseCheckAggregates(pstate, qry);
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return qry;
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}
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/*
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* transformInsertStmt -
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* transform an Insert Statement
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*/
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static Query *
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transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
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{
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Query *qry = makeNode(Query);
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SelectStmt *selectStmt = (SelectStmt *) stmt->selectStmt;
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List *exprList = NIL;
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bool isGeneralSelect;
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List *sub_rtable;
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List *sub_namespace;
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List *icolumns;
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List *attrnos;
|
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ParseNamespaceItem *nsitem;
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RangeTblEntry *rte;
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ListCell *icols;
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ListCell *attnos;
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ListCell *lc;
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bool isOnConflictUpdate;
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AclMode targetPerms;
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/* There can't be any outer WITH to worry about */
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Assert(pstate->p_ctenamespace == NIL);
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qry->commandType = CMD_INSERT;
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pstate->p_is_insert = true;
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/* process the WITH clause independently of all else */
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if (stmt->withClause)
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{
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qry->hasRecursive = stmt->withClause->recursive;
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qry->cteList = transformWithClause(pstate, stmt->withClause);
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qry->hasModifyingCTE = pstate->p_hasModifyingCTE;
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}
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qry->override = stmt->override;
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isOnConflictUpdate = (stmt->onConflictClause &&
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stmt->onConflictClause->action == ONCONFLICT_UPDATE);
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|
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/*
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* We have three cases to deal with: DEFAULT VALUES (selectStmt == NULL),
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* VALUES list, or general SELECT input. We special-case VALUES, both for
|
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* efficiency and so we can handle DEFAULT specifications.
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*
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* The grammar allows attaching ORDER BY, LIMIT, FOR UPDATE, or WITH to a
|
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* VALUES clause. If we have any of those, treat it as a general SELECT;
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* so it will work, but you can't use DEFAULT items together with those.
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*/
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isGeneralSelect = (selectStmt && (selectStmt->valuesLists == NIL ||
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selectStmt->sortClause != NIL ||
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selectStmt->limitOffset != NULL ||
|
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selectStmt->limitCount != NULL ||
|
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selectStmt->lockingClause != NIL ||
|
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selectStmt->withClause != NULL));
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|
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/*
|
|
* If a non-nil rangetable/namespace was passed in, and we are doing
|
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* INSERT/SELECT, arrange to pass the rangetable/namespace down to the
|
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* SELECT. This can only happen if we are inside a CREATE RULE, and in
|
|
* that case we want the rule's OLD and NEW rtable entries to appear as
|
|
* part of the SELECT's rtable, not as outer references for it. (Kluge!)
|
|
* The SELECT's joinlist is not affected however. We must do this before
|
|
* adding the target table to the INSERT's rtable.
|
|
*/
|
|
if (isGeneralSelect)
|
|
{
|
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sub_rtable = pstate->p_rtable;
|
|
pstate->p_rtable = NIL;
|
|
sub_namespace = pstate->p_namespace;
|
|
pstate->p_namespace = NIL;
|
|
}
|
|
else
|
|
{
|
|
sub_rtable = NIL; /* not used, but keep compiler quiet */
|
|
sub_namespace = NIL;
|
|
}
|
|
|
|
/*
|
|
* Must get write lock on INSERT target table before scanning SELECT, else
|
|
* we will grab the wrong kind of initial lock if the target table is also
|
|
* mentioned in the SELECT part. Note that the target table is not added
|
|
* to the joinlist or namespace.
|
|
*/
|
|
targetPerms = ACL_INSERT;
|
|
if (isOnConflictUpdate)
|
|
targetPerms |= ACL_UPDATE;
|
|
qry->resultRelation = setTargetTable(pstate, stmt->relation,
|
|
false, false, targetPerms);
|
|
|
|
/* Validate stmt->cols list, or build default list if no list given */
|
|
icolumns = checkInsertTargets(pstate, stmt->cols, &attrnos);
|
|
Assert(list_length(icolumns) == list_length(attrnos));
|
|
|
|
/*
|
|
* Determine which variant of INSERT we have.
|
|
*/
|
|
if (selectStmt == NULL)
|
|
{
|
|
/*
|
|
* We have INSERT ... DEFAULT VALUES. We can handle this case by
|
|
* emitting an empty targetlist --- all columns will be defaulted when
|
|
* the planner expands the targetlist.
|
|
*/
|
|
exprList = NIL;
|
|
}
|
|
else if (isGeneralSelect)
|
|
{
|
|
/*
|
|
* We make the sub-pstate a child of the outer pstate so that it can
|
|
* see any Param definitions supplied from above. Since the outer
|
|
* pstate's rtable and namespace are presently empty, there are no
|
|
* side-effects of exposing names the sub-SELECT shouldn't be able to
|
|
* see.
|
|
*/
|
|
ParseState *sub_pstate = make_parsestate(pstate);
|
|
Query *selectQuery;
|
|
|
|
/*
|
|
* Process the source SELECT.
|
|
*
|
|
* It is important that this be handled just like a standalone SELECT;
|
|
* otherwise the behavior of SELECT within INSERT might be different
|
|
* from a stand-alone SELECT. (Indeed, Postgres up through 6.5 had
|
|
* bugs of just that nature...)
|
|
*
|
|
* The sole exception is that we prevent resolving unknown-type
|
|
* outputs as TEXT. This does not change the semantics since if the
|
|
* column type matters semantically, it would have been resolved to
|
|
* something else anyway. Doing this lets us resolve such outputs as
|
|
* the target column's type, which we handle below.
|
|
*/
|
|
sub_pstate->p_rtable = sub_rtable;
|
|
sub_pstate->p_joinexprs = NIL; /* sub_rtable has no joins */
|
|
sub_pstate->p_namespace = sub_namespace;
|
|
sub_pstate->p_resolve_unknowns = false;
|
|
|
|
selectQuery = transformStmt(sub_pstate, stmt->selectStmt);
|
|
|
|
free_parsestate(sub_pstate);
|
|
|
|
/* The grammar should have produced a SELECT */
|
|
if (!IsA(selectQuery, Query) ||
|
|
selectQuery->commandType != CMD_SELECT)
|
|
elog(ERROR, "unexpected non-SELECT command in INSERT ... SELECT");
|
|
|
|
/*
|
|
* Make the source be a subquery in the INSERT's rangetable, and add
|
|
* it to the INSERT's joinlist (but not the namespace).
|
|
*/
|
|
nsitem = addRangeTableEntryForSubquery(pstate,
|
|
selectQuery,
|
|
makeAlias("*SELECT*", NIL),
|
|
false,
|
|
false);
|
|
addNSItemToQuery(pstate, nsitem, true, false, false);
|
|
|
|
/*----------
|
|
* Generate an expression list for the INSERT that selects all the
|
|
* non-resjunk columns from the subquery. (INSERT's tlist must be
|
|
* separate from the subquery's tlist because we may add columns,
|
|
* insert datatype coercions, etc.)
|
|
*
|
|
* HACK: unknown-type constants and params in the SELECT's targetlist
|
|
* are copied up as-is rather than being referenced as subquery
|
|
* outputs. This is to ensure that when we try to coerce them to
|
|
* the target column's datatype, the right things happen (see
|
|
* special cases in coerce_type). Otherwise, this fails:
|
|
* INSERT INTO foo SELECT 'bar', ... FROM baz
|
|
*----------
|
|
*/
|
|
exprList = NIL;
|
|
foreach(lc, selectQuery->targetList)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(lc);
|
|
Expr *expr;
|
|
|
|
if (tle->resjunk)
|
|
continue;
|
|
if (tle->expr &&
|
|
(IsA(tle->expr, Const) || IsA(tle->expr, Param)) &&
|
|
exprType((Node *) tle->expr) == UNKNOWNOID)
|
|
expr = tle->expr;
|
|
else
|
|
{
|
|
Var *var = makeVarFromTargetEntry(nsitem->p_rtindex, tle);
|
|
|
|
var->location = exprLocation((Node *) tle->expr);
|
|
expr = (Expr *) var;
|
|
}
|
|
exprList = lappend(exprList, expr);
|
|
}
|
|
|
|
/* Prepare row for assignment to target table */
|
|
exprList = transformInsertRow(pstate, exprList,
|
|
stmt->cols,
|
|
icolumns, attrnos,
|
|
false);
|
|
}
|
|
else if (list_length(selectStmt->valuesLists) > 1)
|
|
{
|
|
/*
|
|
* Process INSERT ... VALUES with multiple VALUES sublists. We
|
|
* generate a VALUES RTE holding the transformed expression lists, and
|
|
* build up a targetlist containing Vars that reference the VALUES
|
|
* RTE.
|
|
*/
|
|
List *exprsLists = NIL;
|
|
List *coltypes = NIL;
|
|
List *coltypmods = NIL;
|
|
List *colcollations = NIL;
|
|
int sublist_length = -1;
|
|
bool lateral = false;
|
|
|
|
Assert(selectStmt->intoClause == NULL);
|
|
|
|
foreach(lc, selectStmt->valuesLists)
|
|
{
|
|
List *sublist = (List *) lfirst(lc);
|
|
|
|
/*
|
|
* Do basic expression transformation (same as a ROW() expr, but
|
|
* allow SetToDefault at top level)
|
|
*/
|
|
sublist = transformExpressionList(pstate, sublist,
|
|
EXPR_KIND_VALUES, true);
|
|
|
|
/*
|
|
* All the sublists must be the same length, *after*
|
|
* transformation (which might expand '*' into multiple items).
|
|
* The VALUES RTE can't handle anything different.
|
|
*/
|
|
if (sublist_length < 0)
|
|
{
|
|
/* Remember post-transformation length of first sublist */
|
|
sublist_length = list_length(sublist);
|
|
}
|
|
else if (sublist_length != list_length(sublist))
|
|
{
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("VALUES lists must all be the same length"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) sublist))));
|
|
}
|
|
|
|
/*
|
|
* Prepare row for assignment to target table. We process any
|
|
* indirection on the target column specs normally but then strip
|
|
* off the resulting field/array assignment nodes, since we don't
|
|
* want the parsed statement to contain copies of those in each
|
|
* VALUES row. (It's annoying to have to transform the
|
|
* indirection specs over and over like this, but avoiding it
|
|
* would take some really messy refactoring of
|
|
* transformAssignmentIndirection.)
|
|
*/
|
|
sublist = transformInsertRow(pstate, sublist,
|
|
stmt->cols,
|
|
icolumns, attrnos,
|
|
true);
|
|
|
|
/*
|
|
* We must assign collations now because assign_query_collations
|
|
* doesn't process rangetable entries. We just assign all the
|
|
* collations independently in each row, and don't worry about
|
|
* whether they are consistent vertically. The outer INSERT query
|
|
* isn't going to care about the collations of the VALUES columns,
|
|
* so it's not worth the effort to identify a common collation for
|
|
* each one here. (But note this does have one user-visible
|
|
* consequence: INSERT ... VALUES won't complain about conflicting
|
|
* explicit COLLATEs in a column, whereas the same VALUES
|
|
* construct in another context would complain.)
|
|
*/
|
|
assign_list_collations(pstate, sublist);
|
|
|
|
exprsLists = lappend(exprsLists, sublist);
|
|
}
|
|
|
|
/*
|
|
* Construct column type/typmod/collation lists for the VALUES RTE.
|
|
* Every expression in each column has been coerced to the type/typmod
|
|
* of the corresponding target column or subfield, so it's sufficient
|
|
* to look at the exprType/exprTypmod of the first row. We don't care
|
|
* about the collation labeling, so just fill in InvalidOid for that.
|
|
*/
|
|
foreach(lc, (List *) linitial(exprsLists))
|
|
{
|
|
Node *val = (Node *) lfirst(lc);
|
|
|
|
coltypes = lappend_oid(coltypes, exprType(val));
|
|
coltypmods = lappend_int(coltypmods, exprTypmod(val));
|
|
colcollations = lappend_oid(colcollations, InvalidOid);
|
|
}
|
|
|
|
/*
|
|
* Ordinarily there can't be any current-level Vars in the expression
|
|
* lists, because the namespace was empty ... but if we're inside
|
|
* CREATE RULE, then NEW/OLD references might appear. In that case we
|
|
* have to mark the VALUES RTE as LATERAL.
|
|
*/
|
|
if (list_length(pstate->p_rtable) != 1 &&
|
|
contain_vars_of_level((Node *) exprsLists, 0))
|
|
lateral = true;
|
|
|
|
/*
|
|
* Generate the VALUES RTE
|
|
*/
|
|
nsitem = addRangeTableEntryForValues(pstate, exprsLists,
|
|
coltypes, coltypmods, colcollations,
|
|
NULL, lateral, true);
|
|
addNSItemToQuery(pstate, nsitem, true, false, false);
|
|
|
|
/*
|
|
* Generate list of Vars referencing the RTE
|
|
*/
|
|
exprList = expandNSItemVars(nsitem, 0, -1, NULL);
|
|
|
|
/*
|
|
* Re-apply any indirection on the target column specs to the Vars
|
|
*/
|
|
exprList = transformInsertRow(pstate, exprList,
|
|
stmt->cols,
|
|
icolumns, attrnos,
|
|
false);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Process INSERT ... VALUES with a single VALUES sublist. We treat
|
|
* this case separately for efficiency. The sublist is just computed
|
|
* directly as the Query's targetlist, with no VALUES RTE. So it
|
|
* works just like a SELECT without any FROM.
|
|
*/
|
|
List *valuesLists = selectStmt->valuesLists;
|
|
|
|
Assert(list_length(valuesLists) == 1);
|
|
Assert(selectStmt->intoClause == NULL);
|
|
|
|
/*
|
|
* Do basic expression transformation (same as a ROW() expr, but allow
|
|
* SetToDefault at top level)
|
|
*/
|
|
exprList = transformExpressionList(pstate,
|
|
(List *) linitial(valuesLists),
|
|
EXPR_KIND_VALUES_SINGLE,
|
|
true);
|
|
|
|
/* Prepare row for assignment to target table */
|
|
exprList = transformInsertRow(pstate, exprList,
|
|
stmt->cols,
|
|
icolumns, attrnos,
|
|
false);
|
|
}
|
|
|
|
/*
|
|
* Generate query's target list using the computed list of expressions.
|
|
* Also, mark all the target columns as needing insert permissions.
|
|
*/
|
|
rte = pstate->p_target_nsitem->p_rte;
|
|
qry->targetList = NIL;
|
|
Assert(list_length(exprList) <= list_length(icolumns));
|
|
forthree(lc, exprList, icols, icolumns, attnos, attrnos)
|
|
{
|
|
Expr *expr = (Expr *) lfirst(lc);
|
|
ResTarget *col = lfirst_node(ResTarget, icols);
|
|
AttrNumber attr_num = (AttrNumber) lfirst_int(attnos);
|
|
TargetEntry *tle;
|
|
|
|
tle = makeTargetEntry(expr,
|
|
attr_num,
|
|
col->name,
|
|
false);
|
|
qry->targetList = lappend(qry->targetList, tle);
|
|
|
|
rte->insertedCols = bms_add_member(rte->insertedCols,
|
|
attr_num - FirstLowInvalidHeapAttributeNumber);
|
|
}
|
|
|
|
/* Process ON CONFLICT, if any. */
|
|
if (stmt->onConflictClause)
|
|
qry->onConflict = transformOnConflictClause(pstate,
|
|
stmt->onConflictClause);
|
|
|
|
/*
|
|
* If we have a RETURNING clause, we need to add the target relation to
|
|
* the query namespace before processing it, so that Var references in
|
|
* RETURNING will work. Also, remove any namespace entries added in a
|
|
* sub-SELECT or VALUES list.
|
|
*/
|
|
if (stmt->returningList)
|
|
{
|
|
pstate->p_namespace = NIL;
|
|
addNSItemToQuery(pstate, pstate->p_target_nsitem,
|
|
false, true, true);
|
|
qry->returningList = transformReturningList(pstate,
|
|
stmt->returningList);
|
|
}
|
|
|
|
/* done building the range table and jointree */
|
|
qry->rtable = pstate->p_rtable;
|
|
qry->jointree = makeFromExpr(pstate->p_joinlist, NULL);
|
|
|
|
qry->hasTargetSRFs = pstate->p_hasTargetSRFs;
|
|
qry->hasSubLinks = pstate->p_hasSubLinks;
|
|
|
|
assign_query_collations(pstate, qry);
|
|
|
|
return qry;
|
|
}
|
|
|
|
/*
|
|
* Prepare an INSERT row for assignment to the target table.
|
|
*
|
|
* exprlist: transformed expressions for source values; these might come from
|
|
* a VALUES row, or be Vars referencing a sub-SELECT or VALUES RTE output.
|
|
* stmtcols: original target-columns spec for INSERT (we just test for NIL)
|
|
* icolumns: effective target-columns spec (list of ResTarget)
|
|
* attrnos: integer column numbers (must be same length as icolumns)
|
|
* strip_indirection: if true, remove any field/array assignment nodes
|
|
*/
|
|
static List *
|
|
transformInsertRow(ParseState *pstate, List *exprlist,
|
|
List *stmtcols, List *icolumns, List *attrnos,
|
|
bool strip_indirection)
|
|
{
|
|
List *result;
|
|
ListCell *lc;
|
|
ListCell *icols;
|
|
ListCell *attnos;
|
|
|
|
/*
|
|
* Check length of expr list. It must not have more expressions than
|
|
* there are target columns. We allow fewer, but only if no explicit
|
|
* columns list was given (the remaining columns are implicitly
|
|
* defaulted). Note we must check this *after* transformation because
|
|
* that could expand '*' into multiple items.
|
|
*/
|
|
if (list_length(exprlist) > list_length(icolumns))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("INSERT has more expressions than target columns"),
|
|
parser_errposition(pstate,
|
|
exprLocation(list_nth(exprlist,
|
|
list_length(icolumns))))));
|
|
if (stmtcols != NIL &&
|
|
list_length(exprlist) < list_length(icolumns))
|
|
{
|
|
/*
|
|
* We can get here for cases like INSERT ... SELECT (a,b,c) FROM ...
|
|
* where the user accidentally created a RowExpr instead of separate
|
|
* columns. Add a suitable hint if that seems to be the problem,
|
|
* because the main error message is quite misleading for this case.
|
|
* (If there's no stmtcols, you'll get something about data type
|
|
* mismatch, which is less misleading so we don't worry about giving a
|
|
* hint in that case.)
|
|
*/
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("INSERT has more target columns than expressions"),
|
|
((list_length(exprlist) == 1 &&
|
|
count_rowexpr_columns(pstate, linitial(exprlist)) ==
|
|
list_length(icolumns)) ?
|
|
errhint("The insertion source is a row expression containing the same number of columns expected by the INSERT. Did you accidentally use extra parentheses?") : 0),
|
|
parser_errposition(pstate,
|
|
exprLocation(list_nth(icolumns,
|
|
list_length(exprlist))))));
|
|
}
|
|
|
|
/*
|
|
* Prepare columns for assignment to target table.
|
|
*/
|
|
result = NIL;
|
|
forthree(lc, exprlist, icols, icolumns, attnos, attrnos)
|
|
{
|
|
Expr *expr = (Expr *) lfirst(lc);
|
|
ResTarget *col = lfirst_node(ResTarget, icols);
|
|
int attno = lfirst_int(attnos);
|
|
|
|
expr = transformAssignedExpr(pstate, expr,
|
|
EXPR_KIND_INSERT_TARGET,
|
|
col->name,
|
|
attno,
|
|
col->indirection,
|
|
col->location);
|
|
|
|
if (strip_indirection)
|
|
{
|
|
while (expr)
|
|
{
|
|
if (IsA(expr, FieldStore))
|
|
{
|
|
FieldStore *fstore = (FieldStore *) expr;
|
|
|
|
expr = (Expr *) linitial(fstore->newvals);
|
|
}
|
|
else if (IsA(expr, SubscriptingRef))
|
|
{
|
|
SubscriptingRef *sbsref = (SubscriptingRef *) expr;
|
|
|
|
if (sbsref->refassgnexpr == NULL)
|
|
break;
|
|
|
|
expr = sbsref->refassgnexpr;
|
|
}
|
|
else
|
|
break;
|
|
}
|
|
}
|
|
|
|
result = lappend(result, expr);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* transformOnConflictClause -
|
|
* transforms an OnConflictClause in an INSERT
|
|
*/
|
|
static OnConflictExpr *
|
|
transformOnConflictClause(ParseState *pstate,
|
|
OnConflictClause *onConflictClause)
|
|
{
|
|
List *arbiterElems;
|
|
Node *arbiterWhere;
|
|
Oid arbiterConstraint;
|
|
List *onConflictSet = NIL;
|
|
Node *onConflictWhere = NULL;
|
|
int exclRelIndex = 0;
|
|
List *exclRelTlist = NIL;
|
|
OnConflictExpr *result;
|
|
|
|
/* Process the arbiter clause, ON CONFLICT ON (...) */
|
|
transformOnConflictArbiter(pstate, onConflictClause, &arbiterElems,
|
|
&arbiterWhere, &arbiterConstraint);
|
|
|
|
/* Process DO UPDATE */
|
|
if (onConflictClause->action == ONCONFLICT_UPDATE)
|
|
{
|
|
Relation targetrel = pstate->p_target_relation;
|
|
ParseNamespaceItem *exclNSItem;
|
|
RangeTblEntry *exclRte;
|
|
|
|
/*
|
|
* All INSERT expressions have been parsed, get ready for potentially
|
|
* existing SET statements that need to be processed like an UPDATE.
|
|
*/
|
|
pstate->p_is_insert = false;
|
|
|
|
/*
|
|
* Add range table entry for the EXCLUDED pseudo relation. relkind is
|
|
* set to composite to signal that we're not dealing with an actual
|
|
* relation, and no permission checks are required on it. (We'll
|
|
* check the actual target relation, instead.)
|
|
*/
|
|
exclNSItem = addRangeTableEntryForRelation(pstate,
|
|
targetrel,
|
|
RowExclusiveLock,
|
|
makeAlias("excluded", NIL),
|
|
false, false);
|
|
exclRte = exclNSItem->p_rte;
|
|
exclRelIndex = exclNSItem->p_rtindex;
|
|
|
|
exclRte->relkind = RELKIND_COMPOSITE_TYPE;
|
|
exclRte->requiredPerms = 0;
|
|
/* other permissions fields in exclRte are already empty */
|
|
|
|
/* Create EXCLUDED rel's targetlist for use by EXPLAIN */
|
|
exclRelTlist = BuildOnConflictExcludedTargetlist(targetrel,
|
|
exclRelIndex);
|
|
|
|
/*
|
|
* Add EXCLUDED and the target RTE to the namespace, so that they can
|
|
* be used in the UPDATE subexpressions.
|
|
*/
|
|
addNSItemToQuery(pstate, exclNSItem, false, true, true);
|
|
addNSItemToQuery(pstate, pstate->p_target_nsitem,
|
|
false, true, true);
|
|
|
|
/*
|
|
* Now transform the UPDATE subexpressions.
|
|
*/
|
|
onConflictSet =
|
|
transformUpdateTargetList(pstate, onConflictClause->targetList);
|
|
|
|
onConflictWhere = transformWhereClause(pstate,
|
|
onConflictClause->whereClause,
|
|
EXPR_KIND_WHERE, "WHERE");
|
|
}
|
|
|
|
/* Finally, build ON CONFLICT DO [NOTHING | UPDATE] expression */
|
|
result = makeNode(OnConflictExpr);
|
|
|
|
result->action = onConflictClause->action;
|
|
result->arbiterElems = arbiterElems;
|
|
result->arbiterWhere = arbiterWhere;
|
|
result->constraint = arbiterConstraint;
|
|
result->onConflictSet = onConflictSet;
|
|
result->onConflictWhere = onConflictWhere;
|
|
result->exclRelIndex = exclRelIndex;
|
|
result->exclRelTlist = exclRelTlist;
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
/*
|
|
* BuildOnConflictExcludedTargetlist
|
|
* Create target list for the EXCLUDED pseudo-relation of ON CONFLICT,
|
|
* representing the columns of targetrel with varno exclRelIndex.
|
|
*
|
|
* Note: Exported for use in the rewriter.
|
|
*/
|
|
List *
|
|
BuildOnConflictExcludedTargetlist(Relation targetrel,
|
|
Index exclRelIndex)
|
|
{
|
|
List *result = NIL;
|
|
int attno;
|
|
Var *var;
|
|
TargetEntry *te;
|
|
|
|
/*
|
|
* Note that resnos of the tlist must correspond to attnos of the
|
|
* underlying relation, hence we need entries for dropped columns too.
|
|
*/
|
|
for (attno = 0; attno < RelationGetNumberOfAttributes(targetrel); attno++)
|
|
{
|
|
Form_pg_attribute attr = TupleDescAttr(targetrel->rd_att, attno);
|
|
char *name;
|
|
|
|
if (attr->attisdropped)
|
|
{
|
|
/*
|
|
* can't use atttypid here, but it doesn't really matter what type
|
|
* the Const claims to be.
|
|
*/
|
|
var = (Var *) makeNullConst(INT4OID, -1, InvalidOid);
|
|
name = NULL;
|
|
}
|
|
else
|
|
{
|
|
var = makeVar(exclRelIndex, attno + 1,
|
|
attr->atttypid, attr->atttypmod,
|
|
attr->attcollation,
|
|
0);
|
|
name = pstrdup(NameStr(attr->attname));
|
|
}
|
|
|
|
te = makeTargetEntry((Expr *) var,
|
|
attno + 1,
|
|
name,
|
|
false);
|
|
|
|
result = lappend(result, te);
|
|
}
|
|
|
|
/*
|
|
* Add a whole-row-Var entry to support references to "EXCLUDED.*". Like
|
|
* the other entries in the EXCLUDED tlist, its resno must match the Var's
|
|
* varattno, else the wrong things happen while resolving references in
|
|
* setrefs.c. This is against normal conventions for targetlists, but
|
|
* it's okay since we don't use this as a real tlist.
|
|
*/
|
|
var = makeVar(exclRelIndex, InvalidAttrNumber,
|
|
targetrel->rd_rel->reltype,
|
|
-1, InvalidOid, 0);
|
|
te = makeTargetEntry((Expr *) var, InvalidAttrNumber, NULL, true);
|
|
result = lappend(result, te);
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
/*
|
|
* count_rowexpr_columns -
|
|
* get number of columns contained in a ROW() expression;
|
|
* return -1 if expression isn't a RowExpr or a Var referencing one.
|
|
*
|
|
* This is currently used only for hint purposes, so we aren't terribly
|
|
* tense about recognizing all possible cases. The Var case is interesting
|
|
* because that's what we'll get in the INSERT ... SELECT (...) case.
|
|
*/
|
|
static int
|
|
count_rowexpr_columns(ParseState *pstate, Node *expr)
|
|
{
|
|
if (expr == NULL)
|
|
return -1;
|
|
if (IsA(expr, RowExpr))
|
|
return list_length(((RowExpr *) expr)->args);
|
|
if (IsA(expr, Var))
|
|
{
|
|
Var *var = (Var *) expr;
|
|
AttrNumber attnum = var->varattno;
|
|
|
|
if (attnum > 0 && var->vartype == RECORDOID)
|
|
{
|
|
RangeTblEntry *rte;
|
|
|
|
rte = GetRTEByRangeTablePosn(pstate, var->varno, var->varlevelsup);
|
|
if (rte->rtekind == RTE_SUBQUERY)
|
|
{
|
|
/* Subselect-in-FROM: examine sub-select's output expr */
|
|
TargetEntry *ste = get_tle_by_resno(rte->subquery->targetList,
|
|
attnum);
|
|
|
|
if (ste == NULL || ste->resjunk)
|
|
return -1;
|
|
expr = (Node *) ste->expr;
|
|
if (IsA(expr, RowExpr))
|
|
return list_length(((RowExpr *) expr)->args);
|
|
}
|
|
}
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
|
|
/*
|
|
* transformSelectStmt -
|
|
* transforms a Select Statement
|
|
*
|
|
* Note: this covers only cases with no set operations and no VALUES lists;
|
|
* see below for the other cases.
|
|
*/
|
|
static Query *
|
|
transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
|
|
{
|
|
Query *qry = makeNode(Query);
|
|
Node *qual;
|
|
ListCell *l;
|
|
|
|
qry->commandType = CMD_SELECT;
|
|
|
|
/* process the WITH clause independently of all else */
|
|
if (stmt->withClause)
|
|
{
|
|
qry->hasRecursive = stmt->withClause->recursive;
|
|
qry->cteList = transformWithClause(pstate, stmt->withClause);
|
|
qry->hasModifyingCTE = pstate->p_hasModifyingCTE;
|
|
}
|
|
|
|
/* Complain if we get called from someplace where INTO is not allowed */
|
|
if (stmt->intoClause)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("SELECT ... INTO is not allowed here"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) stmt->intoClause))));
|
|
|
|
/* make FOR UPDATE/FOR SHARE info available to addRangeTableEntry */
|
|
pstate->p_locking_clause = stmt->lockingClause;
|
|
|
|
/* make WINDOW info available for window functions, too */
|
|
pstate->p_windowdefs = stmt->windowClause;
|
|
|
|
/* process the FROM clause */
|
|
transformFromClause(pstate, stmt->fromClause);
|
|
|
|
/* transform targetlist */
|
|
qry->targetList = transformTargetList(pstate, stmt->targetList,
|
|
EXPR_KIND_SELECT_TARGET);
|
|
|
|
/* mark column origins */
|
|
markTargetListOrigins(pstate, qry->targetList);
|
|
|
|
/* transform WHERE */
|
|
qual = transformWhereClause(pstate, stmt->whereClause,
|
|
EXPR_KIND_WHERE, "WHERE");
|
|
|
|
/* initial processing of HAVING clause is much like WHERE clause */
|
|
qry->havingQual = transformWhereClause(pstate, stmt->havingClause,
|
|
EXPR_KIND_HAVING, "HAVING");
|
|
|
|
/*
|
|
* Transform sorting/grouping stuff. Do ORDER BY first because both
|
|
* transformGroupClause and transformDistinctClause need the results. Note
|
|
* that these functions can also change the targetList, so it's passed to
|
|
* them by reference.
|
|
*/
|
|
qry->sortClause = transformSortClause(pstate,
|
|
stmt->sortClause,
|
|
&qry->targetList,
|
|
EXPR_KIND_ORDER_BY,
|
|
false /* allow SQL92 rules */ );
|
|
|
|
qry->groupClause = transformGroupClause(pstate,
|
|
stmt->groupClause,
|
|
&qry->groupingSets,
|
|
&qry->targetList,
|
|
qry->sortClause,
|
|
EXPR_KIND_GROUP_BY,
|
|
false /* allow SQL92 rules */ );
|
|
|
|
if (stmt->distinctClause == NIL)
|
|
{
|
|
qry->distinctClause = NIL;
|
|
qry->hasDistinctOn = false;
|
|
}
|
|
else if (linitial(stmt->distinctClause) == NULL)
|
|
{
|
|
/* We had SELECT DISTINCT */
|
|
qry->distinctClause = transformDistinctClause(pstate,
|
|
&qry->targetList,
|
|
qry->sortClause,
|
|
false);
|
|
qry->hasDistinctOn = false;
|
|
}
|
|
else
|
|
{
|
|
/* We had SELECT DISTINCT ON */
|
|
qry->distinctClause = transformDistinctOnClause(pstate,
|
|
stmt->distinctClause,
|
|
&qry->targetList,
|
|
qry->sortClause);
|
|
qry->hasDistinctOn = true;
|
|
}
|
|
|
|
/* transform LIMIT */
|
|
qry->limitOffset = transformLimitClause(pstate, stmt->limitOffset,
|
|
EXPR_KIND_OFFSET, "OFFSET",
|
|
stmt->limitOption);
|
|
qry->limitCount = transformLimitClause(pstate, stmt->limitCount,
|
|
EXPR_KIND_LIMIT, "LIMIT",
|
|
stmt->limitOption);
|
|
qry->limitOption = stmt->limitOption;
|
|
|
|
/* transform window clauses after we have seen all window functions */
|
|
qry->windowClause = transformWindowDefinitions(pstate,
|
|
pstate->p_windowdefs,
|
|
&qry->targetList);
|
|
|
|
/* resolve any still-unresolved output columns as being type text */
|
|
if (pstate->p_resolve_unknowns)
|
|
resolveTargetListUnknowns(pstate, qry->targetList);
|
|
|
|
qry->rtable = pstate->p_rtable;
|
|
qry->jointree = makeFromExpr(pstate->p_joinlist, qual);
|
|
|
|
qry->hasSubLinks = pstate->p_hasSubLinks;
|
|
qry->hasWindowFuncs = pstate->p_hasWindowFuncs;
|
|
qry->hasTargetSRFs = pstate->p_hasTargetSRFs;
|
|
qry->hasAggs = pstate->p_hasAggs;
|
|
|
|
foreach(l, stmt->lockingClause)
|
|
{
|
|
transformLockingClause(pstate, qry,
|
|
(LockingClause *) lfirst(l), false);
|
|
}
|
|
|
|
assign_query_collations(pstate, qry);
|
|
|
|
/* this must be done after collations, for reliable comparison of exprs */
|
|
if (pstate->p_hasAggs || qry->groupClause || qry->groupingSets || qry->havingQual)
|
|
parseCheckAggregates(pstate, qry);
|
|
|
|
return qry;
|
|
}
|
|
|
|
/*
|
|
* transformValuesClause -
|
|
* transforms a VALUES clause that's being used as a standalone SELECT
|
|
*
|
|
* We build a Query containing a VALUES RTE, rather as if one had written
|
|
* SELECT * FROM (VALUES ...) AS "*VALUES*"
|
|
*/
|
|
static Query *
|
|
transformValuesClause(ParseState *pstate, SelectStmt *stmt)
|
|
{
|
|
Query *qry = makeNode(Query);
|
|
List *exprsLists;
|
|
List *coltypes = NIL;
|
|
List *coltypmods = NIL;
|
|
List *colcollations = NIL;
|
|
List **colexprs = NULL;
|
|
int sublist_length = -1;
|
|
bool lateral = false;
|
|
ParseNamespaceItem *nsitem;
|
|
ListCell *lc;
|
|
ListCell *lc2;
|
|
int i;
|
|
|
|
qry->commandType = CMD_SELECT;
|
|
|
|
/* Most SELECT stuff doesn't apply in a VALUES clause */
|
|
Assert(stmt->distinctClause == NIL);
|
|
Assert(stmt->intoClause == NULL);
|
|
Assert(stmt->targetList == NIL);
|
|
Assert(stmt->fromClause == NIL);
|
|
Assert(stmt->whereClause == NULL);
|
|
Assert(stmt->groupClause == NIL);
|
|
Assert(stmt->havingClause == NULL);
|
|
Assert(stmt->windowClause == NIL);
|
|
Assert(stmt->op == SETOP_NONE);
|
|
|
|
/* process the WITH clause independently of all else */
|
|
if (stmt->withClause)
|
|
{
|
|
qry->hasRecursive = stmt->withClause->recursive;
|
|
qry->cteList = transformWithClause(pstate, stmt->withClause);
|
|
qry->hasModifyingCTE = pstate->p_hasModifyingCTE;
|
|
}
|
|
|
|
/*
|
|
* For each row of VALUES, transform the raw expressions.
|
|
*
|
|
* Note that the intermediate representation we build is column-organized
|
|
* not row-organized. That simplifies the type and collation processing
|
|
* below.
|
|
*/
|
|
foreach(lc, stmt->valuesLists)
|
|
{
|
|
List *sublist = (List *) lfirst(lc);
|
|
|
|
/*
|
|
* Do basic expression transformation (same as a ROW() expr, but here
|
|
* we disallow SetToDefault)
|
|
*/
|
|
sublist = transformExpressionList(pstate, sublist,
|
|
EXPR_KIND_VALUES, false);
|
|
|
|
/*
|
|
* All the sublists must be the same length, *after* transformation
|
|
* (which might expand '*' into multiple items). The VALUES RTE can't
|
|
* handle anything different.
|
|
*/
|
|
if (sublist_length < 0)
|
|
{
|
|
/* Remember post-transformation length of first sublist */
|
|
sublist_length = list_length(sublist);
|
|
/* and allocate array for per-column lists */
|
|
colexprs = (List **) palloc0(sublist_length * sizeof(List *));
|
|
}
|
|
else if (sublist_length != list_length(sublist))
|
|
{
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("VALUES lists must all be the same length"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) sublist))));
|
|
}
|
|
|
|
/* Build per-column expression lists */
|
|
i = 0;
|
|
foreach(lc2, sublist)
|
|
{
|
|
Node *col = (Node *) lfirst(lc2);
|
|
|
|
colexprs[i] = lappend(colexprs[i], col);
|
|
i++;
|
|
}
|
|
|
|
/* Release sub-list's cells to save memory */
|
|
list_free(sublist);
|
|
}
|
|
|
|
/*
|
|
* Now resolve the common types of the columns, and coerce everything to
|
|
* those types. Then identify the common typmod and common collation, if
|
|
* any, of each column.
|
|
*
|
|
* We must do collation processing now because (1) assign_query_collations
|
|
* doesn't process rangetable entries, and (2) we need to label the VALUES
|
|
* RTE with column collations for use in the outer query. We don't
|
|
* consider conflict of implicit collations to be an error here; instead
|
|
* the column will just show InvalidOid as its collation, and you'll get a
|
|
* failure later if that results in failure to resolve a collation.
|
|
*
|
|
* Note we modify the per-column expression lists in-place.
|
|
*/
|
|
for (i = 0; i < sublist_length; i++)
|
|
{
|
|
Oid coltype;
|
|
int32 coltypmod = -1;
|
|
Oid colcoll;
|
|
bool first = true;
|
|
|
|
coltype = select_common_type(pstate, colexprs[i], "VALUES", NULL);
|
|
|
|
foreach(lc, colexprs[i])
|
|
{
|
|
Node *col = (Node *) lfirst(lc);
|
|
|
|
col = coerce_to_common_type(pstate, col, coltype, "VALUES");
|
|
lfirst(lc) = (void *) col;
|
|
if (first)
|
|
{
|
|
coltypmod = exprTypmod(col);
|
|
first = false;
|
|
}
|
|
else
|
|
{
|
|
/* As soon as we see a non-matching typmod, fall back to -1 */
|
|
if (coltypmod >= 0 && coltypmod != exprTypmod(col))
|
|
coltypmod = -1;
|
|
}
|
|
}
|
|
|
|
colcoll = select_common_collation(pstate, colexprs[i], true);
|
|
|
|
coltypes = lappend_oid(coltypes, coltype);
|
|
coltypmods = lappend_int(coltypmods, coltypmod);
|
|
colcollations = lappend_oid(colcollations, colcoll);
|
|
}
|
|
|
|
/*
|
|
* Finally, rearrange the coerced expressions into row-organized lists.
|
|
*/
|
|
exprsLists = NIL;
|
|
foreach(lc, colexprs[0])
|
|
{
|
|
Node *col = (Node *) lfirst(lc);
|
|
List *sublist;
|
|
|
|
sublist = list_make1(col);
|
|
exprsLists = lappend(exprsLists, sublist);
|
|
}
|
|
list_free(colexprs[0]);
|
|
for (i = 1; i < sublist_length; i++)
|
|
{
|
|
forboth(lc, colexprs[i], lc2, exprsLists)
|
|
{
|
|
Node *col = (Node *) lfirst(lc);
|
|
List *sublist = lfirst(lc2);
|
|
|
|
/* sublist pointer in exprsLists won't need adjustment */
|
|
(void) lappend(sublist, col);
|
|
}
|
|
list_free(colexprs[i]);
|
|
}
|
|
|
|
/*
|
|
* Ordinarily there can't be any current-level Vars in the expression
|
|
* lists, because the namespace was empty ... but if we're inside CREATE
|
|
* RULE, then NEW/OLD references might appear. In that case we have to
|
|
* mark the VALUES RTE as LATERAL.
|
|
*/
|
|
if (pstate->p_rtable != NIL &&
|
|
contain_vars_of_level((Node *) exprsLists, 0))
|
|
lateral = true;
|
|
|
|
/*
|
|
* Generate the VALUES RTE
|
|
*/
|
|
nsitem = addRangeTableEntryForValues(pstate, exprsLists,
|
|
coltypes, coltypmods, colcollations,
|
|
NULL, lateral, true);
|
|
addNSItemToQuery(pstate, nsitem, true, true, true);
|
|
|
|
/*
|
|
* Generate a targetlist as though expanding "*"
|
|
*/
|
|
Assert(pstate->p_next_resno == 1);
|
|
qry->targetList = expandNSItemAttrs(pstate, nsitem, 0, -1);
|
|
|
|
/*
|
|
* The grammar allows attaching ORDER BY, LIMIT, and FOR UPDATE to a
|
|
* VALUES, so cope.
|
|
*/
|
|
qry->sortClause = transformSortClause(pstate,
|
|
stmt->sortClause,
|
|
&qry->targetList,
|
|
EXPR_KIND_ORDER_BY,
|
|
false /* allow SQL92 rules */ );
|
|
|
|
qry->limitOffset = transformLimitClause(pstate, stmt->limitOffset,
|
|
EXPR_KIND_OFFSET, "OFFSET",
|
|
stmt->limitOption);
|
|
qry->limitCount = transformLimitClause(pstate, stmt->limitCount,
|
|
EXPR_KIND_LIMIT, "LIMIT",
|
|
stmt->limitOption);
|
|
qry->limitOption = stmt->limitOption;
|
|
|
|
if (stmt->lockingClause)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s cannot be applied to VALUES",
|
|
LCS_asString(((LockingClause *)
|
|
linitial(stmt->lockingClause))->strength))));
|
|
|
|
qry->rtable = pstate->p_rtable;
|
|
qry->jointree = makeFromExpr(pstate->p_joinlist, NULL);
|
|
|
|
qry->hasSubLinks = pstate->p_hasSubLinks;
|
|
|
|
assign_query_collations(pstate, qry);
|
|
|
|
return qry;
|
|
}
|
|
|
|
/*
|
|
* transformSetOperationStmt -
|
|
* transforms a set-operations tree
|
|
*
|
|
* A set-operation tree is just a SELECT, but with UNION/INTERSECT/EXCEPT
|
|
* structure to it. We must transform each leaf SELECT and build up a top-
|
|
* level Query that contains the leaf SELECTs as subqueries in its rangetable.
|
|
* The tree of set operations is converted into the setOperations field of
|
|
* the top-level Query.
|
|
*/
|
|
static Query *
|
|
transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt)
|
|
{
|
|
Query *qry = makeNode(Query);
|
|
SelectStmt *leftmostSelect;
|
|
int leftmostRTI;
|
|
Query *leftmostQuery;
|
|
SetOperationStmt *sostmt;
|
|
List *sortClause;
|
|
Node *limitOffset;
|
|
Node *limitCount;
|
|
List *lockingClause;
|
|
WithClause *withClause;
|
|
Node *node;
|
|
ListCell *left_tlist,
|
|
*lct,
|
|
*lcm,
|
|
*lcc,
|
|
*l;
|
|
List *targetvars,
|
|
*targetnames,
|
|
*sv_namespace;
|
|
int sv_rtable_length;
|
|
ParseNamespaceItem *jnsitem;
|
|
ParseNamespaceColumn *sortnscolumns;
|
|
int sortcolindex;
|
|
int tllen;
|
|
|
|
qry->commandType = CMD_SELECT;
|
|
|
|
/*
|
|
* Find leftmost leaf SelectStmt. We currently only need to do this in
|
|
* order to deliver a suitable error message if there's an INTO clause
|
|
* there, implying the set-op tree is in a context that doesn't allow
|
|
* INTO. (transformSetOperationTree would throw error anyway, but it
|
|
* seems worth the trouble to throw a different error for non-leftmost
|
|
* INTO, so we produce that error in transformSetOperationTree.)
|
|
*/
|
|
leftmostSelect = stmt->larg;
|
|
while (leftmostSelect && leftmostSelect->op != SETOP_NONE)
|
|
leftmostSelect = leftmostSelect->larg;
|
|
Assert(leftmostSelect && IsA(leftmostSelect, SelectStmt) &&
|
|
leftmostSelect->larg == NULL);
|
|
if (leftmostSelect->intoClause)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("SELECT ... INTO is not allowed here"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) leftmostSelect->intoClause))));
|
|
|
|
/*
|
|
* We need to extract ORDER BY and other top-level clauses here and not
|
|
* let transformSetOperationTree() see them --- else it'll just recurse
|
|
* right back here!
|
|
*/
|
|
sortClause = stmt->sortClause;
|
|
limitOffset = stmt->limitOffset;
|
|
limitCount = stmt->limitCount;
|
|
lockingClause = stmt->lockingClause;
|
|
withClause = stmt->withClause;
|
|
|
|
stmt->sortClause = NIL;
|
|
stmt->limitOffset = NULL;
|
|
stmt->limitCount = NULL;
|
|
stmt->lockingClause = NIL;
|
|
stmt->withClause = NULL;
|
|
|
|
/* We don't support FOR UPDATE/SHARE with set ops at the moment. */
|
|
if (lockingClause)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with UNION/INTERSECT/EXCEPT",
|
|
LCS_asString(((LockingClause *)
|
|
linitial(lockingClause))->strength))));
|
|
|
|
/* Process the WITH clause independently of all else */
|
|
if (withClause)
|
|
{
|
|
qry->hasRecursive = withClause->recursive;
|
|
qry->cteList = transformWithClause(pstate, withClause);
|
|
qry->hasModifyingCTE = pstate->p_hasModifyingCTE;
|
|
}
|
|
|
|
/*
|
|
* Recursively transform the components of the tree.
|
|
*/
|
|
sostmt = castNode(SetOperationStmt,
|
|
transformSetOperationTree(pstate, stmt, true, NULL));
|
|
Assert(sostmt);
|
|
qry->setOperations = (Node *) sostmt;
|
|
|
|
/*
|
|
* Re-find leftmost SELECT (now it's a sub-query in rangetable)
|
|
*/
|
|
node = sostmt->larg;
|
|
while (node && IsA(node, SetOperationStmt))
|
|
node = ((SetOperationStmt *) node)->larg;
|
|
Assert(node && IsA(node, RangeTblRef));
|
|
leftmostRTI = ((RangeTblRef *) node)->rtindex;
|
|
leftmostQuery = rt_fetch(leftmostRTI, pstate->p_rtable)->subquery;
|
|
Assert(leftmostQuery != NULL);
|
|
|
|
/*
|
|
* Generate dummy targetlist for outer query using column names of
|
|
* leftmost select and common datatypes/collations of topmost set
|
|
* operation. Also make lists of the dummy vars and their names for use
|
|
* in parsing ORDER BY.
|
|
*
|
|
* Note: we use leftmostRTI as the varno of the dummy variables. It
|
|
* shouldn't matter too much which RT index they have, as long as they
|
|
* have one that corresponds to a real RT entry; else funny things may
|
|
* happen when the tree is mashed by rule rewriting.
|
|
*/
|
|
qry->targetList = NIL;
|
|
targetvars = NIL;
|
|
targetnames = NIL;
|
|
sortnscolumns = (ParseNamespaceColumn *)
|
|
palloc0(list_length(sostmt->colTypes) * sizeof(ParseNamespaceColumn));
|
|
sortcolindex = 0;
|
|
|
|
forfour(lct, sostmt->colTypes,
|
|
lcm, sostmt->colTypmods,
|
|
lcc, sostmt->colCollations,
|
|
left_tlist, leftmostQuery->targetList)
|
|
{
|
|
Oid colType = lfirst_oid(lct);
|
|
int32 colTypmod = lfirst_int(lcm);
|
|
Oid colCollation = lfirst_oid(lcc);
|
|
TargetEntry *lefttle = (TargetEntry *) lfirst(left_tlist);
|
|
char *colName;
|
|
TargetEntry *tle;
|
|
Var *var;
|
|
|
|
Assert(!lefttle->resjunk);
|
|
colName = pstrdup(lefttle->resname);
|
|
var = makeVar(leftmostRTI,
|
|
lefttle->resno,
|
|
colType,
|
|
colTypmod,
|
|
colCollation,
|
|
0);
|
|
var->location = exprLocation((Node *) lefttle->expr);
|
|
tle = makeTargetEntry((Expr *) var,
|
|
(AttrNumber) pstate->p_next_resno++,
|
|
colName,
|
|
false);
|
|
qry->targetList = lappend(qry->targetList, tle);
|
|
targetvars = lappend(targetvars, var);
|
|
targetnames = lappend(targetnames, makeString(colName));
|
|
sortnscolumns[sortcolindex].p_varno = leftmostRTI;
|
|
sortnscolumns[sortcolindex].p_varattno = lefttle->resno;
|
|
sortnscolumns[sortcolindex].p_vartype = colType;
|
|
sortnscolumns[sortcolindex].p_vartypmod = colTypmod;
|
|
sortnscolumns[sortcolindex].p_varcollid = colCollation;
|
|
sortnscolumns[sortcolindex].p_varnosyn = leftmostRTI;
|
|
sortnscolumns[sortcolindex].p_varattnosyn = lefttle->resno;
|
|
sortcolindex++;
|
|
}
|
|
|
|
/*
|
|
* As a first step towards supporting sort clauses that are expressions
|
|
* using the output columns, generate a namespace entry that makes the
|
|
* output columns visible. A Join RTE node is handy for this, since we
|
|
* can easily control the Vars generated upon matches.
|
|
*
|
|
* Note: we don't yet do anything useful with such cases, but at least
|
|
* "ORDER BY upper(foo)" will draw the right error message rather than
|
|
* "foo not found".
|
|
*/
|
|
sv_rtable_length = list_length(pstate->p_rtable);
|
|
|
|
jnsitem = addRangeTableEntryForJoin(pstate,
|
|
targetnames,
|
|
sortnscolumns,
|
|
JOIN_INNER,
|
|
0,
|
|
targetvars,
|
|
NIL,
|
|
NIL,
|
|
NULL,
|
|
false);
|
|
|
|
sv_namespace = pstate->p_namespace;
|
|
pstate->p_namespace = NIL;
|
|
|
|
/* add jnsitem to column namespace only */
|
|
addNSItemToQuery(pstate, jnsitem, false, false, true);
|
|
|
|
/*
|
|
* For now, we don't support resjunk sort clauses on the output of a
|
|
* setOperation tree --- you can only use the SQL92-spec options of
|
|
* selecting an output column by name or number. Enforce by checking that
|
|
* transformSortClause doesn't add any items to tlist.
|
|
*/
|
|
tllen = list_length(qry->targetList);
|
|
|
|
qry->sortClause = transformSortClause(pstate,
|
|
sortClause,
|
|
&qry->targetList,
|
|
EXPR_KIND_ORDER_BY,
|
|
false /* allow SQL92 rules */ );
|
|
|
|
/* restore namespace, remove join RTE from rtable */
|
|
pstate->p_namespace = sv_namespace;
|
|
pstate->p_rtable = list_truncate(pstate->p_rtable, sv_rtable_length);
|
|
|
|
if (tllen != list_length(qry->targetList))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("invalid UNION/INTERSECT/EXCEPT ORDER BY clause"),
|
|
errdetail("Only result column names can be used, not expressions or functions."),
|
|
errhint("Add the expression/function to every SELECT, or move the UNION into a FROM clause."),
|
|
parser_errposition(pstate,
|
|
exprLocation(list_nth(qry->targetList, tllen)))));
|
|
|
|
qry->limitOffset = transformLimitClause(pstate, limitOffset,
|
|
EXPR_KIND_OFFSET, "OFFSET",
|
|
stmt->limitOption);
|
|
qry->limitCount = transformLimitClause(pstate, limitCount,
|
|
EXPR_KIND_LIMIT, "LIMIT",
|
|
stmt->limitOption);
|
|
qry->limitOption = stmt->limitOption;
|
|
|
|
qry->rtable = pstate->p_rtable;
|
|
qry->jointree = makeFromExpr(pstate->p_joinlist, NULL);
|
|
|
|
qry->hasSubLinks = pstate->p_hasSubLinks;
|
|
qry->hasWindowFuncs = pstate->p_hasWindowFuncs;
|
|
qry->hasTargetSRFs = pstate->p_hasTargetSRFs;
|
|
qry->hasAggs = pstate->p_hasAggs;
|
|
|
|
foreach(l, lockingClause)
|
|
{
|
|
transformLockingClause(pstate, qry,
|
|
(LockingClause *) lfirst(l), false);
|
|
}
|
|
|
|
assign_query_collations(pstate, qry);
|
|
|
|
/* this must be done after collations, for reliable comparison of exprs */
|
|
if (pstate->p_hasAggs || qry->groupClause || qry->groupingSets || qry->havingQual)
|
|
parseCheckAggregates(pstate, qry);
|
|
|
|
return qry;
|
|
}
|
|
|
|
/*
|
|
* transformSetOperationTree
|
|
* Recursively transform leaves and internal nodes of a set-op tree
|
|
*
|
|
* In addition to returning the transformed node, if targetlist isn't NULL
|
|
* then we return a list of its non-resjunk TargetEntry nodes. For a leaf
|
|
* set-op node these are the actual targetlist entries; otherwise they are
|
|
* dummy entries created to carry the type, typmod, collation, and location
|
|
* (for error messages) of each output column of the set-op node. This info
|
|
* is needed only during the internal recursion of this function, so outside
|
|
* callers pass NULL for targetlist. Note: the reason for passing the
|
|
* actual targetlist entries of a leaf node is so that upper levels can
|
|
* replace UNKNOWN Consts with properly-coerced constants.
|
|
*/
|
|
static Node *
|
|
transformSetOperationTree(ParseState *pstate, SelectStmt *stmt,
|
|
bool isTopLevel, List **targetlist)
|
|
{
|
|
bool isLeaf;
|
|
|
|
Assert(stmt && IsA(stmt, SelectStmt));
|
|
|
|
/* Guard against stack overflow due to overly complex set-expressions */
|
|
check_stack_depth();
|
|
|
|
/*
|
|
* Validity-check both leaf and internal SELECTs for disallowed ops.
|
|
*/
|
|
if (stmt->intoClause)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("INTO is only allowed on first SELECT of UNION/INTERSECT/EXCEPT"),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) stmt->intoClause))));
|
|
|
|
/* We don't support FOR UPDATE/SHARE with set ops at the moment. */
|
|
if (stmt->lockingClause)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with UNION/INTERSECT/EXCEPT",
|
|
LCS_asString(((LockingClause *)
|
|
linitial(stmt->lockingClause))->strength))));
|
|
|
|
/*
|
|
* If an internal node of a set-op tree has ORDER BY, LIMIT, FOR UPDATE,
|
|
* or WITH clauses attached, we need to treat it like a leaf node to
|
|
* generate an independent sub-Query tree. Otherwise, it can be
|
|
* represented by a SetOperationStmt node underneath the parent Query.
|
|
*/
|
|
if (stmt->op == SETOP_NONE)
|
|
{
|
|
Assert(stmt->larg == NULL && stmt->rarg == NULL);
|
|
isLeaf = true;
|
|
}
|
|
else
|
|
{
|
|
Assert(stmt->larg != NULL && stmt->rarg != NULL);
|
|
if (stmt->sortClause || stmt->limitOffset || stmt->limitCount ||
|
|
stmt->lockingClause || stmt->withClause)
|
|
isLeaf = true;
|
|
else
|
|
isLeaf = false;
|
|
}
|
|
|
|
if (isLeaf)
|
|
{
|
|
/* Process leaf SELECT */
|
|
Query *selectQuery;
|
|
char selectName[32];
|
|
ParseNamespaceItem *nsitem;
|
|
RangeTblRef *rtr;
|
|
ListCell *tl;
|
|
|
|
/*
|
|
* Transform SelectStmt into a Query.
|
|
*
|
|
* This works the same as SELECT transformation normally would, except
|
|
* that we prevent resolving unknown-type outputs as TEXT. This does
|
|
* not change the subquery's semantics since if the column type
|
|
* matters semantically, it would have been resolved to something else
|
|
* anyway. Doing this lets us resolve such outputs using
|
|
* select_common_type(), below.
|
|
*
|
|
* Note: previously transformed sub-queries don't affect the parsing
|
|
* of this sub-query, because they are not in the toplevel pstate's
|
|
* namespace list.
|
|
*/
|
|
selectQuery = parse_sub_analyze((Node *) stmt, pstate,
|
|
NULL, false, false);
|
|
|
|
/*
|
|
* Check for bogus references to Vars on the current query level (but
|
|
* upper-level references are okay). Normally this can't happen
|
|
* because the namespace will be empty, but it could happen if we are
|
|
* inside a rule.
|
|
*/
|
|
if (pstate->p_namespace)
|
|
{
|
|
if (contain_vars_of_level((Node *) selectQuery, 1))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
|
|
errmsg("UNION/INTERSECT/EXCEPT member statement cannot refer to other relations of same query level"),
|
|
parser_errposition(pstate,
|
|
locate_var_of_level((Node *) selectQuery, 1))));
|
|
}
|
|
|
|
/*
|
|
* Extract a list of the non-junk TLEs for upper-level processing.
|
|
*/
|
|
if (targetlist)
|
|
{
|
|
*targetlist = NIL;
|
|
foreach(tl, selectQuery->targetList)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(tl);
|
|
|
|
if (!tle->resjunk)
|
|
*targetlist = lappend(*targetlist, tle);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Make the leaf query be a subquery in the top-level rangetable.
|
|
*/
|
|
snprintf(selectName, sizeof(selectName), "*SELECT* %d",
|
|
list_length(pstate->p_rtable) + 1);
|
|
nsitem = addRangeTableEntryForSubquery(pstate,
|
|
selectQuery,
|
|
makeAlias(selectName, NIL),
|
|
false,
|
|
false);
|
|
|
|
/*
|
|
* Return a RangeTblRef to replace the SelectStmt in the set-op tree.
|
|
*/
|
|
rtr = makeNode(RangeTblRef);
|
|
rtr->rtindex = nsitem->p_rtindex;
|
|
return (Node *) rtr;
|
|
}
|
|
else
|
|
{
|
|
/* Process an internal node (set operation node) */
|
|
SetOperationStmt *op = makeNode(SetOperationStmt);
|
|
List *ltargetlist;
|
|
List *rtargetlist;
|
|
ListCell *ltl;
|
|
ListCell *rtl;
|
|
const char *context;
|
|
|
|
context = (stmt->op == SETOP_UNION ? "UNION" :
|
|
(stmt->op == SETOP_INTERSECT ? "INTERSECT" :
|
|
"EXCEPT"));
|
|
|
|
op->op = stmt->op;
|
|
op->all = stmt->all;
|
|
|
|
/*
|
|
* Recursively transform the left child node.
|
|
*/
|
|
op->larg = transformSetOperationTree(pstate, stmt->larg,
|
|
false,
|
|
<argetlist);
|
|
|
|
/*
|
|
* If we are processing a recursive union query, now is the time to
|
|
* examine the non-recursive term's output columns and mark the
|
|
* containing CTE as having those result columns. We should do this
|
|
* only at the topmost setop of the CTE, of course.
|
|
*/
|
|
if (isTopLevel &&
|
|
pstate->p_parent_cte &&
|
|
pstate->p_parent_cte->cterecursive)
|
|
determineRecursiveColTypes(pstate, op->larg, ltargetlist);
|
|
|
|
/*
|
|
* Recursively transform the right child node.
|
|
*/
|
|
op->rarg = transformSetOperationTree(pstate, stmt->rarg,
|
|
false,
|
|
&rtargetlist);
|
|
|
|
/*
|
|
* Verify that the two children have the same number of non-junk
|
|
* columns, and determine the types of the merged output columns.
|
|
*/
|
|
if (list_length(ltargetlist) != list_length(rtargetlist))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("each %s query must have the same number of columns",
|
|
context),
|
|
parser_errposition(pstate,
|
|
exprLocation((Node *) rtargetlist))));
|
|
|
|
if (targetlist)
|
|
*targetlist = NIL;
|
|
op->colTypes = NIL;
|
|
op->colTypmods = NIL;
|
|
op->colCollations = NIL;
|
|
op->groupClauses = NIL;
|
|
forboth(ltl, ltargetlist, rtl, rtargetlist)
|
|
{
|
|
TargetEntry *ltle = (TargetEntry *) lfirst(ltl);
|
|
TargetEntry *rtle = (TargetEntry *) lfirst(rtl);
|
|
Node *lcolnode = (Node *) ltle->expr;
|
|
Node *rcolnode = (Node *) rtle->expr;
|
|
Oid lcoltype = exprType(lcolnode);
|
|
Oid rcoltype = exprType(rcolnode);
|
|
int32 lcoltypmod = exprTypmod(lcolnode);
|
|
int32 rcoltypmod = exprTypmod(rcolnode);
|
|
Node *bestexpr;
|
|
int bestlocation;
|
|
Oid rescoltype;
|
|
int32 rescoltypmod;
|
|
Oid rescolcoll;
|
|
|
|
/* select common type, same as CASE et al */
|
|
rescoltype = select_common_type(pstate,
|
|
list_make2(lcolnode, rcolnode),
|
|
context,
|
|
&bestexpr);
|
|
bestlocation = exprLocation(bestexpr);
|
|
/* if same type and same typmod, use typmod; else default */
|
|
if (lcoltype == rcoltype && lcoltypmod == rcoltypmod)
|
|
rescoltypmod = lcoltypmod;
|
|
else
|
|
rescoltypmod = -1;
|
|
|
|
/*
|
|
* Verify the coercions are actually possible. If not, we'd fail
|
|
* later anyway, but we want to fail now while we have sufficient
|
|
* context to produce an error cursor position.
|
|
*
|
|
* For all non-UNKNOWN-type cases, we verify coercibility but we
|
|
* don't modify the child's expression, for fear of changing the
|
|
* child query's semantics.
|
|
*
|
|
* If a child expression is an UNKNOWN-type Const or Param, we
|
|
* want to replace it with the coerced expression. This can only
|
|
* happen when the child is a leaf set-op node. It's safe to
|
|
* replace the expression because if the child query's semantics
|
|
* depended on the type of this output column, it'd have already
|
|
* coerced the UNKNOWN to something else. We want to do this
|
|
* because (a) we want to verify that a Const is valid for the
|
|
* target type, or resolve the actual type of an UNKNOWN Param,
|
|
* and (b) we want to avoid unnecessary discrepancies between the
|
|
* output type of the child query and the resolved target type.
|
|
* Such a discrepancy would disable optimization in the planner.
|
|
*
|
|
* If it's some other UNKNOWN-type node, eg a Var, we do nothing
|
|
* (knowing that coerce_to_common_type would fail). The planner
|
|
* is sometimes able to fold an UNKNOWN Var to a constant before
|
|
* it has to coerce the type, so failing now would just break
|
|
* cases that might work.
|
|
*/
|
|
if (lcoltype != UNKNOWNOID)
|
|
lcolnode = coerce_to_common_type(pstate, lcolnode,
|
|
rescoltype, context);
|
|
else if (IsA(lcolnode, Const) ||
|
|
IsA(lcolnode, Param))
|
|
{
|
|
lcolnode = coerce_to_common_type(pstate, lcolnode,
|
|
rescoltype, context);
|
|
ltle->expr = (Expr *) lcolnode;
|
|
}
|
|
|
|
if (rcoltype != UNKNOWNOID)
|
|
rcolnode = coerce_to_common_type(pstate, rcolnode,
|
|
rescoltype, context);
|
|
else if (IsA(rcolnode, Const) ||
|
|
IsA(rcolnode, Param))
|
|
{
|
|
rcolnode = coerce_to_common_type(pstate, rcolnode,
|
|
rescoltype, context);
|
|
rtle->expr = (Expr *) rcolnode;
|
|
}
|
|
|
|
/*
|
|
* Select common collation. A common collation is required for
|
|
* all set operators except UNION ALL; see SQL:2008 7.13 <query
|
|
* expression> Syntax Rule 15c. (If we fail to identify a common
|
|
* collation for a UNION ALL column, the colCollations element
|
|
* will be set to InvalidOid, which may result in a runtime error
|
|
* if something at a higher query level wants to use the column's
|
|
* collation.)
|
|
*/
|
|
rescolcoll = select_common_collation(pstate,
|
|
list_make2(lcolnode, rcolnode),
|
|
(op->op == SETOP_UNION && op->all));
|
|
|
|
/* emit results */
|
|
op->colTypes = lappend_oid(op->colTypes, rescoltype);
|
|
op->colTypmods = lappend_int(op->colTypmods, rescoltypmod);
|
|
op->colCollations = lappend_oid(op->colCollations, rescolcoll);
|
|
|
|
/*
|
|
* For all cases except UNION ALL, identify the grouping operators
|
|
* (and, if available, sorting operators) that will be used to
|
|
* eliminate duplicates.
|
|
*/
|
|
if (op->op != SETOP_UNION || !op->all)
|
|
{
|
|
SortGroupClause *grpcl = makeNode(SortGroupClause);
|
|
Oid sortop;
|
|
Oid eqop;
|
|
bool hashable;
|
|
ParseCallbackState pcbstate;
|
|
|
|
setup_parser_errposition_callback(&pcbstate, pstate,
|
|
bestlocation);
|
|
|
|
/* determine the eqop and optional sortop */
|
|
get_sort_group_operators(rescoltype,
|
|
false, true, false,
|
|
&sortop, &eqop, NULL,
|
|
&hashable);
|
|
|
|
cancel_parser_errposition_callback(&pcbstate);
|
|
|
|
/* we don't have a tlist yet, so can't assign sortgrouprefs */
|
|
grpcl->tleSortGroupRef = 0;
|
|
grpcl->eqop = eqop;
|
|
grpcl->sortop = sortop;
|
|
grpcl->nulls_first = false; /* OK with or without sortop */
|
|
grpcl->hashable = hashable;
|
|
|
|
op->groupClauses = lappend(op->groupClauses, grpcl);
|
|
}
|
|
|
|
/*
|
|
* Construct a dummy tlist entry to return. We use a SetToDefault
|
|
* node for the expression, since it carries exactly the fields
|
|
* needed, but any other expression node type would do as well.
|
|
*/
|
|
if (targetlist)
|
|
{
|
|
SetToDefault *rescolnode = makeNode(SetToDefault);
|
|
TargetEntry *restle;
|
|
|
|
rescolnode->typeId = rescoltype;
|
|
rescolnode->typeMod = rescoltypmod;
|
|
rescolnode->collation = rescolcoll;
|
|
rescolnode->location = bestlocation;
|
|
restle = makeTargetEntry((Expr *) rescolnode,
|
|
0, /* no need to set resno */
|
|
NULL,
|
|
false);
|
|
*targetlist = lappend(*targetlist, restle);
|
|
}
|
|
}
|
|
|
|
return (Node *) op;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Process the outputs of the non-recursive term of a recursive union
|
|
* to set up the parent CTE's columns
|
|
*/
|
|
static void
|
|
determineRecursiveColTypes(ParseState *pstate, Node *larg, List *nrtargetlist)
|
|
{
|
|
Node *node;
|
|
int leftmostRTI;
|
|
Query *leftmostQuery;
|
|
List *targetList;
|
|
ListCell *left_tlist;
|
|
ListCell *nrtl;
|
|
int next_resno;
|
|
|
|
/*
|
|
* Find leftmost leaf SELECT
|
|
*/
|
|
node = larg;
|
|
while (node && IsA(node, SetOperationStmt))
|
|
node = ((SetOperationStmt *) node)->larg;
|
|
Assert(node && IsA(node, RangeTblRef));
|
|
leftmostRTI = ((RangeTblRef *) node)->rtindex;
|
|
leftmostQuery = rt_fetch(leftmostRTI, pstate->p_rtable)->subquery;
|
|
Assert(leftmostQuery != NULL);
|
|
|
|
/*
|
|
* Generate dummy targetlist using column names of leftmost select and
|
|
* dummy result expressions of the non-recursive term.
|
|
*/
|
|
targetList = NIL;
|
|
next_resno = 1;
|
|
|
|
forboth(nrtl, nrtargetlist, left_tlist, leftmostQuery->targetList)
|
|
{
|
|
TargetEntry *nrtle = (TargetEntry *) lfirst(nrtl);
|
|
TargetEntry *lefttle = (TargetEntry *) lfirst(left_tlist);
|
|
char *colName;
|
|
TargetEntry *tle;
|
|
|
|
Assert(!lefttle->resjunk);
|
|
colName = pstrdup(lefttle->resname);
|
|
tle = makeTargetEntry(nrtle->expr,
|
|
next_resno++,
|
|
colName,
|
|
false);
|
|
targetList = lappend(targetList, tle);
|
|
}
|
|
|
|
/* Now build CTE's output column info using dummy targetlist */
|
|
analyzeCTETargetList(pstate, pstate->p_parent_cte, targetList);
|
|
}
|
|
|
|
|
|
/*
|
|
* transformUpdateStmt -
|
|
* transforms an update statement
|
|
*/
|
|
static Query *
|
|
transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
|
|
{
|
|
Query *qry = makeNode(Query);
|
|
ParseNamespaceItem *nsitem;
|
|
Node *qual;
|
|
|
|
qry->commandType = CMD_UPDATE;
|
|
pstate->p_is_insert = false;
|
|
|
|
/* process the WITH clause independently of all else */
|
|
if (stmt->withClause)
|
|
{
|
|
qry->hasRecursive = stmt->withClause->recursive;
|
|
qry->cteList = transformWithClause(pstate, stmt->withClause);
|
|
qry->hasModifyingCTE = pstate->p_hasModifyingCTE;
|
|
}
|
|
|
|
qry->resultRelation = setTargetTable(pstate, stmt->relation,
|
|
stmt->relation->inh,
|
|
true,
|
|
ACL_UPDATE);
|
|
nsitem = pstate->p_target_nsitem;
|
|
|
|
/* subqueries in FROM cannot access the result relation */
|
|
nsitem->p_lateral_only = true;
|
|
nsitem->p_lateral_ok = false;
|
|
|
|
/*
|
|
* the FROM clause is non-standard SQL syntax. We used to be able to do
|
|
* this with REPLACE in POSTQUEL so we keep the feature.
|
|
*/
|
|
transformFromClause(pstate, stmt->fromClause);
|
|
|
|
/* remaining clauses can reference the result relation normally */
|
|
nsitem->p_lateral_only = false;
|
|
nsitem->p_lateral_ok = true;
|
|
|
|
qual = transformWhereClause(pstate, stmt->whereClause,
|
|
EXPR_KIND_WHERE, "WHERE");
|
|
|
|
qry->returningList = transformReturningList(pstate, stmt->returningList);
|
|
|
|
/*
|
|
* Now we are done with SELECT-like processing, and can get on with
|
|
* transforming the target list to match the UPDATE target columns.
|
|
*/
|
|
qry->targetList = transformUpdateTargetList(pstate, stmt->targetList);
|
|
|
|
qry->rtable = pstate->p_rtable;
|
|
qry->jointree = makeFromExpr(pstate->p_joinlist, qual);
|
|
|
|
qry->hasTargetSRFs = pstate->p_hasTargetSRFs;
|
|
qry->hasSubLinks = pstate->p_hasSubLinks;
|
|
|
|
assign_query_collations(pstate, qry);
|
|
|
|
return qry;
|
|
}
|
|
|
|
/*
|
|
* transformUpdateTargetList -
|
|
* handle SET clause in UPDATE/INSERT ... ON CONFLICT UPDATE
|
|
*/
|
|
static List *
|
|
transformUpdateTargetList(ParseState *pstate, List *origTlist)
|
|
{
|
|
List *tlist = NIL;
|
|
RangeTblEntry *target_rte;
|
|
ListCell *orig_tl;
|
|
ListCell *tl;
|
|
TupleDesc tupdesc = pstate->p_target_relation->rd_att;
|
|
|
|
tlist = transformTargetList(pstate, origTlist,
|
|
EXPR_KIND_UPDATE_SOURCE);
|
|
|
|
/* Prepare to assign non-conflicting resnos to resjunk attributes */
|
|
if (pstate->p_next_resno <= RelationGetNumberOfAttributes(pstate->p_target_relation))
|
|
pstate->p_next_resno = RelationGetNumberOfAttributes(pstate->p_target_relation) + 1;
|
|
|
|
/* Prepare non-junk columns for assignment to target table */
|
|
target_rte = pstate->p_target_nsitem->p_rte;
|
|
orig_tl = list_head(origTlist);
|
|
|
|
foreach(tl, tlist)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(tl);
|
|
ResTarget *origTarget;
|
|
int attrno;
|
|
|
|
if (tle->resjunk)
|
|
{
|
|
/*
|
|
* Resjunk nodes need no additional processing, but be sure they
|
|
* have resnos that do not match any target columns; else rewriter
|
|
* or planner might get confused. They don't need a resname
|
|
* either.
|
|
*/
|
|
tle->resno = (AttrNumber) pstate->p_next_resno++;
|
|
tle->resname = NULL;
|
|
continue;
|
|
}
|
|
if (orig_tl == NULL)
|
|
elog(ERROR, "UPDATE target count mismatch --- internal error");
|
|
origTarget = lfirst_node(ResTarget, orig_tl);
|
|
|
|
attrno = attnameAttNum(pstate->p_target_relation,
|
|
origTarget->name, true);
|
|
if (attrno == InvalidAttrNumber)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_COLUMN),
|
|
errmsg("column \"%s\" of relation \"%s\" does not exist",
|
|
origTarget->name,
|
|
RelationGetRelationName(pstate->p_target_relation)),
|
|
parser_errposition(pstate, origTarget->location)));
|
|
|
|
updateTargetListEntry(pstate, tle, origTarget->name,
|
|
attrno,
|
|
origTarget->indirection,
|
|
origTarget->location);
|
|
|
|
/* Mark the target column as requiring update permissions */
|
|
target_rte->updatedCols = bms_add_member(target_rte->updatedCols,
|
|
attrno - FirstLowInvalidHeapAttributeNumber);
|
|
|
|
orig_tl = lnext(origTlist, orig_tl);
|
|
}
|
|
if (orig_tl != NULL)
|
|
elog(ERROR, "UPDATE target count mismatch --- internal error");
|
|
|
|
fill_extraUpdatedCols(target_rte, tupdesc);
|
|
|
|
return tlist;
|
|
}
|
|
|
|
/*
|
|
* Record in extraUpdatedCols generated columns referencing updated base
|
|
* columns.
|
|
*/
|
|
void
|
|
fill_extraUpdatedCols(RangeTblEntry *target_rte, TupleDesc tupdesc)
|
|
{
|
|
if (tupdesc->constr &&
|
|
tupdesc->constr->has_generated_stored)
|
|
{
|
|
for (int i = 0; i < tupdesc->constr->num_defval; i++)
|
|
{
|
|
AttrDefault defval = tupdesc->constr->defval[i];
|
|
Node *expr;
|
|
Bitmapset *attrs_used = NULL;
|
|
|
|
/* skip if not generated column */
|
|
if (!TupleDescAttr(tupdesc, defval.adnum - 1)->attgenerated)
|
|
continue;
|
|
|
|
expr = stringToNode(defval.adbin);
|
|
pull_varattnos(expr, 1, &attrs_used);
|
|
|
|
if (bms_overlap(target_rte->updatedCols, attrs_used))
|
|
target_rte->extraUpdatedCols = bms_add_member(target_rte->extraUpdatedCols,
|
|
defval.adnum - FirstLowInvalidHeapAttributeNumber);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* transformReturningList -
|
|
* handle a RETURNING clause in INSERT/UPDATE/DELETE
|
|
*/
|
|
static List *
|
|
transformReturningList(ParseState *pstate, List *returningList)
|
|
{
|
|
List *rlist;
|
|
int save_next_resno;
|
|
|
|
if (returningList == NIL)
|
|
return NIL; /* nothing to do */
|
|
|
|
/*
|
|
* We need to assign resnos starting at one in the RETURNING list. Save
|
|
* and restore the main tlist's value of p_next_resno, just in case
|
|
* someone looks at it later (probably won't happen).
|
|
*/
|
|
save_next_resno = pstate->p_next_resno;
|
|
pstate->p_next_resno = 1;
|
|
|
|
/* transform RETURNING identically to a SELECT targetlist */
|
|
rlist = transformTargetList(pstate, returningList, EXPR_KIND_RETURNING);
|
|
|
|
/*
|
|
* Complain if the nonempty tlist expanded to nothing (which is possible
|
|
* if it contains only a star-expansion of a zero-column table). If we
|
|
* allow this, the parsed Query will look like it didn't have RETURNING,
|
|
* with results that would probably surprise the user.
|
|
*/
|
|
if (rlist == NIL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("RETURNING must have at least one column"),
|
|
parser_errposition(pstate,
|
|
exprLocation(linitial(returningList)))));
|
|
|
|
/* mark column origins */
|
|
markTargetListOrigins(pstate, rlist);
|
|
|
|
/* resolve any still-unresolved output columns as being type text */
|
|
if (pstate->p_resolve_unknowns)
|
|
resolveTargetListUnknowns(pstate, rlist);
|
|
|
|
/* restore state */
|
|
pstate->p_next_resno = save_next_resno;
|
|
|
|
return rlist;
|
|
}
|
|
|
|
|
|
/*
|
|
* transformDeclareCursorStmt -
|
|
* transform a DECLARE CURSOR Statement
|
|
*
|
|
* DECLARE CURSOR is like other utility statements in that we emit it as a
|
|
* CMD_UTILITY Query node; however, we must first transform the contained
|
|
* query. We used to postpone that until execution, but it's really necessary
|
|
* to do it during the normal parse analysis phase to ensure that side effects
|
|
* of parser hooks happen at the expected time.
|
|
*/
|
|
static Query *
|
|
transformDeclareCursorStmt(ParseState *pstate, DeclareCursorStmt *stmt)
|
|
{
|
|
Query *result;
|
|
Query *query;
|
|
|
|
/*
|
|
* Don't allow both SCROLL and NO SCROLL to be specified
|
|
*/
|
|
if ((stmt->options & CURSOR_OPT_SCROLL) &&
|
|
(stmt->options & CURSOR_OPT_NO_SCROLL))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_CURSOR_DEFINITION),
|
|
errmsg("cannot specify both SCROLL and NO SCROLL")));
|
|
|
|
/* Transform contained query, not allowing SELECT INTO */
|
|
query = transformStmt(pstate, stmt->query);
|
|
stmt->query = (Node *) query;
|
|
|
|
/* Grammar should not have allowed anything but SELECT */
|
|
if (!IsA(query, Query) ||
|
|
query->commandType != CMD_SELECT)
|
|
elog(ERROR, "unexpected non-SELECT command in DECLARE CURSOR");
|
|
|
|
/*
|
|
* We also disallow data-modifying WITH in a cursor. (This could be
|
|
* allowed, but the semantics of when the updates occur might be
|
|
* surprising.)
|
|
*/
|
|
if (query->hasModifyingCTE)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("DECLARE CURSOR must not contain data-modifying statements in WITH")));
|
|
|
|
/* FOR UPDATE and WITH HOLD are not compatible */
|
|
if (query->rowMarks != NIL && (stmt->options & CURSOR_OPT_HOLD))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("DECLARE CURSOR WITH HOLD ... %s is not supported",
|
|
LCS_asString(((RowMarkClause *)
|
|
linitial(query->rowMarks))->strength)),
|
|
errdetail("Holdable cursors must be READ ONLY.")));
|
|
|
|
/* FOR UPDATE and SCROLL are not compatible */
|
|
if (query->rowMarks != NIL && (stmt->options & CURSOR_OPT_SCROLL))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("DECLARE SCROLL CURSOR ... %s is not supported",
|
|
LCS_asString(((RowMarkClause *)
|
|
linitial(query->rowMarks))->strength)),
|
|
errdetail("Scrollable cursors must be READ ONLY.")));
|
|
|
|
/* FOR UPDATE and INSENSITIVE are not compatible */
|
|
if (query->rowMarks != NIL && (stmt->options & CURSOR_OPT_INSENSITIVE))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("DECLARE INSENSITIVE CURSOR ... %s is not supported",
|
|
LCS_asString(((RowMarkClause *)
|
|
linitial(query->rowMarks))->strength)),
|
|
errdetail("Insensitive cursors must be READ ONLY.")));
|
|
|
|
/* represent the command as a utility Query */
|
|
result = makeNode(Query);
|
|
result->commandType = CMD_UTILITY;
|
|
result->utilityStmt = (Node *) stmt;
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
/*
|
|
* transformExplainStmt -
|
|
* transform an EXPLAIN Statement
|
|
*
|
|
* EXPLAIN is like other utility statements in that we emit it as a
|
|
* CMD_UTILITY Query node; however, we must first transform the contained
|
|
* query. We used to postpone that until execution, but it's really necessary
|
|
* to do it during the normal parse analysis phase to ensure that side effects
|
|
* of parser hooks happen at the expected time.
|
|
*/
|
|
static Query *
|
|
transformExplainStmt(ParseState *pstate, ExplainStmt *stmt)
|
|
{
|
|
Query *result;
|
|
|
|
/* transform contained query, allowing SELECT INTO */
|
|
stmt->query = (Node *) transformOptionalSelectInto(pstate, stmt->query);
|
|
|
|
/* represent the command as a utility Query */
|
|
result = makeNode(Query);
|
|
result->commandType = CMD_UTILITY;
|
|
result->utilityStmt = (Node *) stmt;
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
/*
|
|
* transformCreateTableAsStmt -
|
|
* transform a CREATE TABLE AS, SELECT ... INTO, or CREATE MATERIALIZED VIEW
|
|
* Statement
|
|
*
|
|
* As with DECLARE CURSOR and EXPLAIN, transform the contained statement now.
|
|
*/
|
|
static Query *
|
|
transformCreateTableAsStmt(ParseState *pstate, CreateTableAsStmt *stmt)
|
|
{
|
|
Query *result;
|
|
Query *query;
|
|
|
|
/* transform contained query, not allowing SELECT INTO */
|
|
query = transformStmt(pstate, stmt->query);
|
|
stmt->query = (Node *) query;
|
|
|
|
/* additional work needed for CREATE MATERIALIZED VIEW */
|
|
if (stmt->objtype == OBJECT_MATVIEW)
|
|
{
|
|
/*
|
|
* Prohibit a data-modifying CTE in the query used to create a
|
|
* materialized view. It's not sufficiently clear what the user would
|
|
* want to happen if the MV is refreshed or incrementally maintained.
|
|
*/
|
|
if (query->hasModifyingCTE)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("materialized views must not use data-modifying statements in WITH")));
|
|
|
|
/*
|
|
* Check whether any temporary database objects are used in the
|
|
* creation query. It would be hard to refresh data or incrementally
|
|
* maintain it if a source disappeared.
|
|
*/
|
|
if (isQueryUsingTempRelation(query))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("materialized views must not use temporary tables or views")));
|
|
|
|
/*
|
|
* A materialized view would either need to save parameters for use in
|
|
* maintaining/loading the data or prohibit them entirely. The latter
|
|
* seems safer and more sane.
|
|
*/
|
|
if (query_contains_extern_params(query))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("materialized views may not be defined using bound parameters")));
|
|
|
|
/*
|
|
* For now, we disallow unlogged materialized views, because it seems
|
|
* like a bad idea for them to just go to empty after a crash. (If we
|
|
* could mark them as unpopulated, that would be better, but that
|
|
* requires catalog changes which crash recovery can't presently
|
|
* handle.)
|
|
*/
|
|
if (stmt->into->rel->relpersistence == RELPERSISTENCE_UNLOGGED)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("materialized views cannot be unlogged")));
|
|
|
|
/*
|
|
* At runtime, we'll need a copy of the parsed-but-not-rewritten Query
|
|
* for purposes of creating the view's ON SELECT rule. We stash that
|
|
* in the IntoClause because that's where intorel_startup() can
|
|
* conveniently get it from.
|
|
*/
|
|
stmt->into->viewQuery = (Node *) copyObject(query);
|
|
}
|
|
|
|
/* represent the command as a utility Query */
|
|
result = makeNode(Query);
|
|
result->commandType = CMD_UTILITY;
|
|
result->utilityStmt = (Node *) stmt;
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* transform a CallStmt
|
|
*
|
|
* We need to do parse analysis on the procedure call and its arguments.
|
|
*/
|
|
static Query *
|
|
transformCallStmt(ParseState *pstate, CallStmt *stmt)
|
|
{
|
|
List *targs;
|
|
ListCell *lc;
|
|
Node *node;
|
|
Query *result;
|
|
|
|
targs = NIL;
|
|
foreach(lc, stmt->funccall->args)
|
|
{
|
|
targs = lappend(targs, transformExpr(pstate,
|
|
(Node *) lfirst(lc),
|
|
EXPR_KIND_CALL_ARGUMENT));
|
|
}
|
|
|
|
node = ParseFuncOrColumn(pstate,
|
|
stmt->funccall->funcname,
|
|
targs,
|
|
pstate->p_last_srf,
|
|
stmt->funccall,
|
|
true,
|
|
stmt->funccall->location);
|
|
|
|
assign_expr_collations(pstate, node);
|
|
|
|
stmt->funcexpr = castNode(FuncExpr, node);
|
|
|
|
result = makeNode(Query);
|
|
result->commandType = CMD_UTILITY;
|
|
result->utilityStmt = (Node *) stmt;
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Produce a string representation of a LockClauseStrength value.
|
|
* This should only be applied to valid values (not LCS_NONE).
|
|
*/
|
|
const char *
|
|
LCS_asString(LockClauseStrength strength)
|
|
{
|
|
switch (strength)
|
|
{
|
|
case LCS_NONE:
|
|
Assert(false);
|
|
break;
|
|
case LCS_FORKEYSHARE:
|
|
return "FOR KEY SHARE";
|
|
case LCS_FORSHARE:
|
|
return "FOR SHARE";
|
|
case LCS_FORNOKEYUPDATE:
|
|
return "FOR NO KEY UPDATE";
|
|
case LCS_FORUPDATE:
|
|
return "FOR UPDATE";
|
|
}
|
|
return "FOR some"; /* shouldn't happen */
|
|
}
|
|
|
|
/*
|
|
* Check for features that are not supported with FOR [KEY] UPDATE/SHARE.
|
|
*
|
|
* exported so planner can check again after rewriting, query pullup, etc
|
|
*/
|
|
void
|
|
CheckSelectLocking(Query *qry, LockClauseStrength strength)
|
|
{
|
|
Assert(strength != LCS_NONE); /* else caller error */
|
|
|
|
if (qry->setOperations)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with UNION/INTERSECT/EXCEPT",
|
|
LCS_asString(strength))));
|
|
if (qry->distinctClause != NIL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with DISTINCT clause",
|
|
LCS_asString(strength))));
|
|
if (qry->groupClause != NIL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with GROUP BY clause",
|
|
LCS_asString(strength))));
|
|
if (qry->havingQual != NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with HAVING clause",
|
|
LCS_asString(strength))));
|
|
if (qry->hasAggs)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with aggregate functions",
|
|
LCS_asString(strength))));
|
|
if (qry->hasWindowFuncs)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with window functions",
|
|
LCS_asString(strength))));
|
|
if (qry->hasTargetSRFs)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s is not allowed with set-returning functions in the target list",
|
|
LCS_asString(strength))));
|
|
}
|
|
|
|
/*
|
|
* Transform a FOR [KEY] UPDATE/SHARE clause
|
|
*
|
|
* This basically involves replacing names by integer relids.
|
|
*
|
|
* NB: if you need to change this, see also markQueryForLocking()
|
|
* in rewriteHandler.c, and isLockedRefname() in parse_relation.c.
|
|
*/
|
|
static void
|
|
transformLockingClause(ParseState *pstate, Query *qry, LockingClause *lc,
|
|
bool pushedDown)
|
|
{
|
|
List *lockedRels = lc->lockedRels;
|
|
ListCell *l;
|
|
ListCell *rt;
|
|
Index i;
|
|
LockingClause *allrels;
|
|
|
|
CheckSelectLocking(qry, lc->strength);
|
|
|
|
/* make a clause we can pass down to subqueries to select all rels */
|
|
allrels = makeNode(LockingClause);
|
|
allrels->lockedRels = NIL; /* indicates all rels */
|
|
allrels->strength = lc->strength;
|
|
allrels->waitPolicy = lc->waitPolicy;
|
|
|
|
if (lockedRels == NIL)
|
|
{
|
|
/* all regular tables used in query */
|
|
i = 0;
|
|
foreach(rt, qry->rtable)
|
|
{
|
|
RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt);
|
|
|
|
++i;
|
|
switch (rte->rtekind)
|
|
{
|
|
case RTE_RELATION:
|
|
applyLockingClause(qry, i, lc->strength, lc->waitPolicy,
|
|
pushedDown);
|
|
rte->requiredPerms |= ACL_SELECT_FOR_UPDATE;
|
|
break;
|
|
case RTE_SUBQUERY:
|
|
applyLockingClause(qry, i, lc->strength, lc->waitPolicy,
|
|
pushedDown);
|
|
|
|
/*
|
|
* FOR UPDATE/SHARE of subquery is propagated to all of
|
|
* subquery's rels, too. We could do this later (based on
|
|
* the marking of the subquery RTE) but it is convenient
|
|
* to have local knowledge in each query level about which
|
|
* rels need to be opened with RowShareLock.
|
|
*/
|
|
transformLockingClause(pstate, rte->subquery,
|
|
allrels, true);
|
|
break;
|
|
default:
|
|
/* ignore JOIN, SPECIAL, FUNCTION, VALUES, CTE RTEs */
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* just the named tables */
|
|
foreach(l, lockedRels)
|
|
{
|
|
RangeVar *thisrel = (RangeVar *) lfirst(l);
|
|
|
|
/* For simplicity we insist on unqualified alias names here */
|
|
if (thisrel->catalogname || thisrel->schemaname)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s must specify unqualified relation names",
|
|
LCS_asString(lc->strength)),
|
|
parser_errposition(pstate, thisrel->location)));
|
|
|
|
i = 0;
|
|
foreach(rt, qry->rtable)
|
|
{
|
|
RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt);
|
|
|
|
++i;
|
|
if (strcmp(rte->eref->aliasname, thisrel->relname) == 0)
|
|
{
|
|
switch (rte->rtekind)
|
|
{
|
|
case RTE_RELATION:
|
|
applyLockingClause(qry, i, lc->strength,
|
|
lc->waitPolicy, pushedDown);
|
|
rte->requiredPerms |= ACL_SELECT_FOR_UPDATE;
|
|
break;
|
|
case RTE_SUBQUERY:
|
|
applyLockingClause(qry, i, lc->strength,
|
|
lc->waitPolicy, pushedDown);
|
|
/* see comment above */
|
|
transformLockingClause(pstate, rte->subquery,
|
|
allrels, true);
|
|
break;
|
|
case RTE_JOIN:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s cannot be applied to a join",
|
|
LCS_asString(lc->strength)),
|
|
parser_errposition(pstate, thisrel->location)));
|
|
break;
|
|
case RTE_FUNCTION:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s cannot be applied to a function",
|
|
LCS_asString(lc->strength)),
|
|
parser_errposition(pstate, thisrel->location)));
|
|
break;
|
|
case RTE_TABLEFUNC:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s cannot be applied to a table function",
|
|
LCS_asString(lc->strength)),
|
|
parser_errposition(pstate, thisrel->location)));
|
|
break;
|
|
case RTE_VALUES:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s cannot be applied to VALUES",
|
|
LCS_asString(lc->strength)),
|
|
parser_errposition(pstate, thisrel->location)));
|
|
break;
|
|
case RTE_CTE:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s cannot be applied to a WITH query",
|
|
LCS_asString(lc->strength)),
|
|
parser_errposition(pstate, thisrel->location)));
|
|
break;
|
|
case RTE_NAMEDTUPLESTORE:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("%s cannot be applied to a named tuplestore",
|
|
LCS_asString(lc->strength)),
|
|
parser_errposition(pstate, thisrel->location)));
|
|
break;
|
|
|
|
/* Shouldn't be possible to see RTE_RESULT here */
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized RTE type: %d",
|
|
(int) rte->rtekind);
|
|
break;
|
|
}
|
|
break; /* out of foreach loop */
|
|
}
|
|
}
|
|
if (rt == NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_UNDEFINED_TABLE),
|
|
/*------
|
|
translator: %s is a SQL row locking clause such as FOR UPDATE */
|
|
errmsg("relation \"%s\" in %s clause not found in FROM clause",
|
|
thisrel->relname,
|
|
LCS_asString(lc->strength)),
|
|
parser_errposition(pstate, thisrel->location)));
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Record locking info for a single rangetable item
|
|
*/
|
|
void
|
|
applyLockingClause(Query *qry, Index rtindex,
|
|
LockClauseStrength strength, LockWaitPolicy waitPolicy,
|
|
bool pushedDown)
|
|
{
|
|
RowMarkClause *rc;
|
|
|
|
Assert(strength != LCS_NONE); /* else caller error */
|
|
|
|
/* If it's an explicit clause, make sure hasForUpdate gets set */
|
|
if (!pushedDown)
|
|
qry->hasForUpdate = true;
|
|
|
|
/* Check for pre-existing entry for same rtindex */
|
|
if ((rc = get_parse_rowmark(qry, rtindex)) != NULL)
|
|
{
|
|
/*
|
|
* If the same RTE is specified with more than one locking strength,
|
|
* use the strongest. (Reasonable, since you can't take both a shared
|
|
* and exclusive lock at the same time; it'll end up being exclusive
|
|
* anyway.)
|
|
*
|
|
* Similarly, if the same RTE is specified with more than one lock
|
|
* wait policy, consider that NOWAIT wins over SKIP LOCKED, which in
|
|
* turn wins over waiting for the lock (the default). This is a bit
|
|
* more debatable but raising an error doesn't seem helpful. (Consider
|
|
* for instance SELECT FOR UPDATE NOWAIT from a view that internally
|
|
* contains a plain FOR UPDATE spec.) Having NOWAIT win over SKIP
|
|
* LOCKED is reasonable since the former throws an error in case of
|
|
* coming across a locked tuple, which may be undesirable in some
|
|
* cases but it seems better than silently returning inconsistent
|
|
* results.
|
|
*
|
|
* And of course pushedDown becomes false if any clause is explicit.
|
|
*/
|
|
rc->strength = Max(rc->strength, strength);
|
|
rc->waitPolicy = Max(rc->waitPolicy, waitPolicy);
|
|
rc->pushedDown &= pushedDown;
|
|
return;
|
|
}
|
|
|
|
/* Make a new RowMarkClause */
|
|
rc = makeNode(RowMarkClause);
|
|
rc->rti = rtindex;
|
|
rc->strength = strength;
|
|
rc->waitPolicy = waitPolicy;
|
|
rc->pushedDown = pushedDown;
|
|
qry->rowMarks = lappend(qry->rowMarks, rc);
|
|
}
|
|
|
|
/*
|
|
* Coverage testing for raw_expression_tree_walker().
|
|
*
|
|
* When enabled, we run raw_expression_tree_walker() over every DML statement
|
|
* submitted to parse analysis. Without this provision, that function is only
|
|
* applied in limited cases involving CTEs, and we don't really want to have
|
|
* to test everything inside as well as outside a CTE.
|
|
*/
|
|
#ifdef RAW_EXPRESSION_COVERAGE_TEST
|
|
|
|
static bool
|
|
test_raw_expression_coverage(Node *node, void *context)
|
|
{
|
|
if (node == NULL)
|
|
return false;
|
|
return raw_expression_tree_walker(node,
|
|
test_raw_expression_coverage,
|
|
context);
|
|
}
|
|
|
|
#endif /* RAW_EXPRESSION_COVERAGE_TEST */
|