Improve plpgsql's error messages for incorrect %TYPE and %ROWTYPE.

If one of these constructs referenced a nonexistent object, we'd fall
through to feeding the whole construct to the core parser, which would
reject it with a "syntax error" message.  That's pretty unhelpful and
misleading.  There's no good reason for plpgsql_parse_wordtype and
friends not to throw a useful error for incorrect input, so make them
do that instead of returning NULL.

Discussion: https://postgr.es/m/1964516.1708977740@sss.pgh.pa.us
This commit is contained in:
Tom Lane 2024-02-28 16:05:17 -05:00
parent 363eb05996
commit 2a6b47cb50
4 changed files with 83 additions and 57 deletions

View File

@ -29,3 +29,39 @@ CREATE OR REPLACE PROCEDURE public.test2(IN x integer)
BEGIN ATOMIC
SELECT (x + 2);
END
-- Test %TYPE and %ROWTYPE error cases
create table misc_table(f1 int);
do $$ declare x foo%type; begin end $$;
ERROR: variable "foo" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x notice%type; begin end $$; -- covers unreserved-keyword case
ERROR: variable "notice" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x foo.bar%type; begin end $$;
ERROR: relation "foo" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x foo.bar.baz%type; begin end $$;
ERROR: schema "foo" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x public.foo.bar%type; begin end $$;
ERROR: relation "public.foo" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x public.misc_table.zed%type; begin end $$;
ERROR: column "zed" of relation "misc_table" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x foo%rowtype; begin end $$;
ERROR: relation "foo" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x notice%rowtype; begin end $$; -- covers unreserved-keyword case
ERROR: relation "notice" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x foo.bar%rowtype; begin end $$;
ERROR: schema "foo" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x foo.bar.baz%rowtype; begin end $$;
ERROR: cross-database references are not implemented: "foo.bar.baz"
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x public.foo%rowtype; begin end $$;
ERROR: relation "public.foo" does not exist
CONTEXT: compilation of PL/pgSQL function "inline_code_block" near line 1
do $$ declare x public.misc_table%rowtype; begin end $$;

View File

@ -1599,7 +1599,7 @@ plpgsql_parse_tripword(char *word1, char *word2, char *word3,
* plpgsql_parse_wordtype The scanner found word%TYPE. word should be
* a pre-existing variable name.
*
* Returns datatype struct, or NULL if no match found for word.
* Returns datatype struct. Throws error if no match found for word.
* ----------
*/
PLpgSQL_type *
@ -1623,15 +1623,15 @@ plpgsql_parse_wordtype(char *ident)
case PLPGSQL_NSTYPE_REC:
return ((PLpgSQL_rec *) (plpgsql_Datums[nse->itemno]))->datatype;
default:
return NULL;
break;
}
}
/*
* Nothing found - up to now it's a word without any special meaning for
* us.
*/
return NULL;
/* No match, complain */
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("variable \"%s\" does not exist", ident)));
return NULL; /* keep compiler quiet */
}
@ -1639,7 +1639,8 @@ plpgsql_parse_wordtype(char *ident)
* plpgsql_parse_cwordtype Same lookup for compositeword%TYPE
*
* Here, we allow either a block-qualified variable name, or a reference
* to a column of some table.
* to a column of some table. (If we must throw error, we assume that the
* latter case was intended.)
* ----------
*/
PLpgSQL_type *
@ -1648,12 +1649,11 @@ plpgsql_parse_cwordtype(List *idents)
PLpgSQL_type *dtype = NULL;
PLpgSQL_nsitem *nse;
int nnames;
const char *fldname;
RangeVar *relvar = NULL;
const char *fldname = NULL;
Oid classOid;
HeapTuple classtup = NULL;
HeapTuple attrtup = NULL;
HeapTuple typetup = NULL;
Form_pg_class classStruct;
Form_pg_attribute attrStruct;
MemoryContext oldCxt;
@ -1688,57 +1688,39 @@ plpgsql_parse_cwordtype(List *idents)
/*
* First word could also be a table name
*/
classOid = RelnameGetRelid(strVal(linitial(idents)));
if (!OidIsValid(classOid))
goto done;
relvar = makeRangeVar(NULL,
strVal(linitial(idents)),
-1);
fldname = strVal(lsecond(idents));
}
else if (list_length(idents) == 3)
else
{
RangeVar *relvar;
/*
* We could check for a block-qualified reference to a field of a
* record variable, but %TYPE is documented as applying to variables,
* not fields of variables. Things would get rather ambiguous if we
* allowed either interpretation.
*/
relvar = makeRangeVar(strVal(linitial(idents)),
strVal(lsecond(idents)),
-1);
/* Can't lock relation - we might not have privileges. */
classOid = RangeVarGetRelid(relvar, NoLock, true);
if (!OidIsValid(classOid))
goto done;
fldname = strVal(lthird(idents));
List *rvnames;
Assert(list_length(idents) > 2);
rvnames = list_delete_last(list_copy(idents));
relvar = makeRangeVarFromNameList(rvnames);
fldname = strVal(llast(idents));
}
else
goto done;
classtup = SearchSysCache1(RELOID, ObjectIdGetDatum(classOid));
if (!HeapTupleIsValid(classtup))
goto done;
classStruct = (Form_pg_class) GETSTRUCT(classtup);
/*
* It must be a relation, sequence, view, materialized view, composite
* type, or foreign table
*/
if (classStruct->relkind != RELKIND_RELATION &&
classStruct->relkind != RELKIND_SEQUENCE &&
classStruct->relkind != RELKIND_VIEW &&
classStruct->relkind != RELKIND_MATVIEW &&
classStruct->relkind != RELKIND_COMPOSITE_TYPE &&
classStruct->relkind != RELKIND_FOREIGN_TABLE &&
classStruct->relkind != RELKIND_PARTITIONED_TABLE)
goto done;
/* Look up relation name. Can't lock it - we might not have privileges. */
classOid = RangeVarGetRelid(relvar, NoLock, false);
/*
* Fetch the named table field and its type
*/
attrtup = SearchSysCacheAttName(classOid, fldname);
if (!HeapTupleIsValid(attrtup))
goto done;
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_COLUMN),
errmsg("column \"%s\" of relation \"%s\" does not exist",
fldname, relvar->relname)));
attrStruct = (Form_pg_attribute) GETSTRUCT(attrtup);
typetup = SearchSysCache1(TYPEOID,
@ -1759,8 +1741,6 @@ plpgsql_parse_cwordtype(List *idents)
MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
done:
if (HeapTupleIsValid(classtup))
ReleaseSysCache(classtup);
if (HeapTupleIsValid(attrtup))
ReleaseSysCache(attrtup);
if (HeapTupleIsValid(typetup))
@ -1824,16 +1804,12 @@ plpgsql_parse_cwordrowtype(List *idents)
* As above, this is a relation lookup but could be a type lookup if we
* weren't being backwards-compatible about error wording.
*/
if (list_length(idents) != 2)
return NULL;
/* Avoid memory leaks in long-term function context */
oldCxt = MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
/* Look up relation name. Can't lock it - we might not have privileges. */
relvar = makeRangeVar(strVal(linitial(idents)),
strVal(lsecond(idents)),
-1);
relvar = makeRangeVarFromNameList(idents);
classOid = RangeVarGetRelid(relvar, NoLock, false);
/* Some relkinds lack type OIDs */
@ -1842,7 +1818,7 @@ plpgsql_parse_cwordrowtype(List *idents)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("relation \"%s\" does not have a composite type",
strVal(lsecond(idents)))));
relvar->relname)));
MemoryContextSwitchTo(oldCxt);

View File

@ -2810,10 +2810,7 @@ read_datatype(int tok)
/*
* If we have a simple or composite identifier, check for %TYPE and
* %ROWTYPE constructs. (Note that if plpgsql_parse_wordtype et al fail
* to recognize the identifier, we'll fall through and pass the whole
* string to parse_datatype, which will assuredly give an unhelpful
* "syntax error". Should we try to give a more specific error?)
* %ROWTYPE constructs.
*/
if (tok == T_WORD)
{

View File

@ -20,3 +20,20 @@ $$;
\sf test1
\sf test2
-- Test %TYPE and %ROWTYPE error cases
create table misc_table(f1 int);
do $$ declare x foo%type; begin end $$;
do $$ declare x notice%type; begin end $$; -- covers unreserved-keyword case
do $$ declare x foo.bar%type; begin end $$;
do $$ declare x foo.bar.baz%type; begin end $$;
do $$ declare x public.foo.bar%type; begin end $$;
do $$ declare x public.misc_table.zed%type; begin end $$;
do $$ declare x foo%rowtype; begin end $$;
do $$ declare x notice%rowtype; begin end $$; -- covers unreserved-keyword case
do $$ declare x foo.bar%rowtype; begin end $$;
do $$ declare x foo.bar.baz%rowtype; begin end $$;
do $$ declare x public.foo%rowtype; begin end $$;
do $$ declare x public.misc_table%rowtype; begin end $$;