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postgresql/src/bin/scripts/reindexdb.c

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/*-------------------------------------------------------------------------
*
* reindexdb
*
* Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
*
* src/bin/scripts/reindexdb.c
*
*-------------------------------------------------------------------------
*/
#include "postgres_fe.h"
#include <limits.h>
#include "catalog/pg_class_d.h"
#include "common.h"
#include "common/connect.h"
#include "common/logging.h"
#include "fe_utils/cancel.h"
#include "fe_utils/option_utils.h"
#include "fe_utils/parallel_slot.h"
#include "fe_utils/query_utils.h"
#include "fe_utils/simple_list.h"
#include "fe_utils/string_utils.h"
typedef enum ReindexType
{
REINDEX_DATABASE,
REINDEX_INDEX,
REINDEX_SCHEMA,
REINDEX_SYSTEM,
REINDEX_TABLE,
} ReindexType;
static SimpleStringList *get_parallel_object_list(PGconn *conn,
ReindexType type,
SimpleStringList *user_list,
bool echo);
static void reindex_one_database(ConnParams *cparams, ReindexType type,
SimpleStringList *user_list,
const char *progname,
bool echo, bool verbose, bool concurrently,
int concurrentCons, const char *tablespace);
static void reindex_all_databases(ConnParams *cparams,
const char *progname, bool echo,
bool quiet, bool verbose, bool concurrently,
int concurrentCons, const char *tablespace,
bool syscatalog, SimpleStringList *schemas,
SimpleStringList *tables,
SimpleStringList *indexes);
static void run_reindex_command(PGconn *conn, ReindexType type,
const char *name, bool echo, bool verbose,
bool concurrently, bool async,
const char *tablespace);
static void help(const char *progname);
int
main(int argc, char *argv[])
{
static struct option long_options[] = {
{"host", required_argument, NULL, 'h'},
{"port", required_argument, NULL, 'p'},
{"username", required_argument, NULL, 'U'},
{"no-password", no_argument, NULL, 'w'},
{"password", no_argument, NULL, 'W'},
{"echo", no_argument, NULL, 'e'},
{"quiet", no_argument, NULL, 'q'},
{"schema", required_argument, NULL, 'S'},
{"dbname", required_argument, NULL, 'd'},
{"all", no_argument, NULL, 'a'},
{"system", no_argument, NULL, 's'},
{"table", required_argument, NULL, 't'},
{"index", required_argument, NULL, 'i'},
{"jobs", required_argument, NULL, 'j'},
{"verbose", no_argument, NULL, 'v'},
{"concurrently", no_argument, NULL, 1},
{"maintenance-db", required_argument, NULL, 2},
{"tablespace", required_argument, NULL, 3},
{NULL, 0, NULL, 0}
};
const char *progname;
int optindex;
int c;
const char *dbname = NULL;
const char *maintenance_db = NULL;
const char *host = NULL;
const char *port = NULL;
const char *username = NULL;
const char *tablespace = NULL;
enum trivalue prompt_password = TRI_DEFAULT;
ConnParams cparams;
bool syscatalog = false;
bool alldb = false;
bool echo = false;
bool quiet = false;
bool verbose = false;
bool concurrently = false;
SimpleStringList indexes = {NULL, NULL};
SimpleStringList tables = {NULL, NULL};
SimpleStringList schemas = {NULL, NULL};
int concurrentCons = 1;
pg_logging_init(argv[0]);
progname = get_progname(argv[0]);
set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pgscripts"));
handle_help_version_opts(argc, argv, "reindexdb", help);
/* process command-line options */
while ((c = getopt_long(argc, argv, "ad:eh:i:j:qp:sS:t:U:vwW", long_options, &optindex)) != -1)
{
switch (c)
{
case 'a':
alldb = true;
break;
case 'd':
dbname = pg_strdup(optarg);
break;
case 'e':
echo = true;
break;
case 'h':
host = pg_strdup(optarg);
break;
case 'i':
simple_string_list_append(&indexes, optarg);
break;
case 'j':
if (!option_parse_int(optarg, "-j/--jobs", 1, INT_MAX,
&concurrentCons))
exit(1);
break;
case 'q':
quiet = true;
break;
case 'p':
port = pg_strdup(optarg);
break;
case 's':
syscatalog = true;
break;
case 'S':
simple_string_list_append(&schemas, optarg);
break;
case 't':
simple_string_list_append(&tables, optarg);
break;
case 'U':
username = pg_strdup(optarg);
break;
case 'v':
verbose = true;
break;
case 'w':
prompt_password = TRI_NO;
break;
case 'W':
prompt_password = TRI_YES;
break;
case 1:
concurrently = true;
break;
case 2:
maintenance_db = pg_strdup(optarg);
break;
case 3:
tablespace = pg_strdup(optarg);
break;
default:
/* getopt_long already emitted a complaint */
pg_log_error_hint("Try \"%s --help\" for more information.", progname);
exit(1);
}
}
/*
* Non-option argument specifies database name as long as it wasn't
* already specified with -d / --dbname
*/
if (optind < argc && dbname == NULL)
{
dbname = argv[optind];
optind++;
}
if (optind < argc)
{
pg_log_error("too many command-line arguments (first is \"%s\")",
argv[optind]);
pg_log_error_hint("Try \"%s --help\" for more information.", progname);
exit(1);
}
/* fill cparams except for dbname, which is set below */
cparams.pghost = host;
cparams.pgport = port;
cparams.pguser = username;
cparams.prompt_password = prompt_password;
cparams.override_dbname = NULL;
setup_cancel_handler(NULL);
if (concurrentCons > 1 && syscatalog)
pg_fatal("cannot use multiple jobs to reindex system catalogs");
if (alldb)
{
if (dbname)
pg_fatal("cannot reindex all databases and a specific one at the same time");
cparams.dbname = maintenance_db;
reindex_all_databases(&cparams, progname, echo, quiet, verbose,
concurrently, concurrentCons, tablespace,
syscatalog, &schemas, &tables, &indexes);
}
else
{
if (dbname == NULL)
{
if (getenv("PGDATABASE"))
dbname = getenv("PGDATABASE");
else if (getenv("PGUSER"))
dbname = getenv("PGUSER");
else
dbname = get_user_name_or_exit(progname);
}
cparams.dbname = dbname;
if (syscatalog)
reindex_one_database(&cparams, REINDEX_SYSTEM, NULL,
progname, echo, verbose,
concurrently, 1, tablespace);
if (schemas.head != NULL)
reindex_one_database(&cparams, REINDEX_SCHEMA, &schemas,
progname, echo, verbose,
concurrently, concurrentCons, tablespace);
if (indexes.head != NULL)
reindex_one_database(&cparams, REINDEX_INDEX, &indexes,
progname, echo, verbose,
concurrently, concurrentCons, tablespace);
if (tables.head != NULL)
reindex_one_database(&cparams, REINDEX_TABLE, &tables,
progname, echo, verbose,
concurrently, concurrentCons, tablespace);
/*
* reindex database only if neither index nor table nor schema nor
* system catalogs is specified
*/
if (!syscatalog && indexes.head == NULL &&
tables.head == NULL && schemas.head == NULL)
reindex_one_database(&cparams, REINDEX_DATABASE, NULL,
progname, echo, verbose,
concurrently, concurrentCons, tablespace);
}
exit(0);
}
static void
reindex_one_database(ConnParams *cparams, ReindexType type,
SimpleStringList *user_list,
const char *progname, bool echo,
bool verbose, bool concurrently, int concurrentCons,
const char *tablespace)
{
PGconn *conn;
SimpleStringListCell *cell;
SimpleStringListCell *indices_tables_cell = NULL;
bool parallel = concurrentCons > 1;
SimpleStringList *process_list = user_list;
SimpleStringList *indices_tables_list = NULL;
ReindexType process_type = type;
ParallelSlotArray *sa;
bool failed = false;
int items_count = 0;
char *prev_index_table_name = NULL;
ParallelSlot *free_slot = NULL;
conn = connectDatabase(cparams, progname, echo, false, true);
if (concurrently && PQserverVersion(conn) < 120000)
{
PQfinish(conn);
pg_fatal("cannot use the \"%s\" option on server versions older than PostgreSQL %s",
"concurrently", "12");
}
if (tablespace && PQserverVersion(conn) < 140000)
{
PQfinish(conn);
pg_fatal("cannot use the \"%s\" option on server versions older than PostgreSQL %s",
"tablespace", "14");
}
if (!parallel)
{
switch (process_type)
{
case REINDEX_DATABASE:
case REINDEX_SYSTEM:
/*
* Database and system reindexes only need to work on the
* database itself, so build a list with a single entry.
*/
Assert(user_list == NULL);
process_list = pg_malloc0(sizeof(SimpleStringList));
simple_string_list_append(process_list, PQdb(conn));
break;
case REINDEX_INDEX:
case REINDEX_SCHEMA:
case REINDEX_TABLE:
Assert(user_list != NULL);
break;
}
}
else
{
switch (process_type)
{
case REINDEX_DATABASE:
/* Build a list of relations from the database */
process_list = get_parallel_object_list(conn, process_type,
user_list, echo);
process_type = REINDEX_TABLE;
/* Bail out if nothing to process */
if (process_list == NULL)
return;
break;
case REINDEX_SCHEMA:
Assert(user_list != NULL);
/* Build a list of relations from all the schemas */
process_list = get_parallel_object_list(conn, process_type,
user_list, echo);
process_type = REINDEX_TABLE;
/* Bail out if nothing to process */
if (process_list == NULL)
return;
break;
case REINDEX_INDEX:
Assert(user_list != NULL);
/*
* Build a list of relations from the indices. This will
* accordingly reorder the list of indices too.
*/
indices_tables_list = get_parallel_object_list(conn, process_type,
user_list, echo);
/*
* Bail out if nothing to process. 'user_list' was modified
* in-place, so check if it has at least one cell.
*/
if (user_list->head == NULL)
return;
/*
* Assuming 'user_list' is not empty, 'indices_tables_list'
* shouldn't be empty as well.
*/
Assert(indices_tables_list != NULL);
indices_tables_cell = indices_tables_list->head;
break;
case REINDEX_SYSTEM:
/* not supported */
Assert(false);
break;
case REINDEX_TABLE:
/*
* Fall through. The list of items for tables is already
* created.
*/
break;
}
}
/*
* Adjust the number of concurrent connections depending on the items in
* the list. We choose the minimum between the number of concurrent
* connections and the number of items in the list.
*/
for (cell = process_list->head; cell; cell = cell->next)
{
items_count++;
/* no need to continue if there are more elements than jobs */
if (items_count >= concurrentCons)
break;
}
concurrentCons = Min(concurrentCons, items_count);
Assert(concurrentCons > 0);
Assert(process_list != NULL);
sa = ParallelSlotsSetup(concurrentCons, cparams, progname, echo, NULL);
ParallelSlotsAdoptConn(sa, conn);
cell = process_list->head;
do
{
const char *objname = cell->val;
bool need_new_slot = true;
if (CancelRequested)
{
failed = true;
goto finish;
}
/*
* For parallel index-level REINDEX, the indices of the same table are
* ordered together and they are to be processed by the same job. So,
* we don't switch the job as soon as the index belongs to the same
* table as the previous one.
*/
if (parallel && process_type == REINDEX_INDEX)
{
if (prev_index_table_name != NULL &&
strcmp(prev_index_table_name, indices_tables_cell->val) == 0)
need_new_slot = false;
prev_index_table_name = indices_tables_cell->val;
indices_tables_cell = indices_tables_cell->next;
}
if (need_new_slot)
{
free_slot = ParallelSlotsGetIdle(sa, NULL);
if (!free_slot)
{
failed = true;
goto finish;
}
ParallelSlotSetHandler(free_slot, TableCommandResultHandler, NULL);
}
run_reindex_command(free_slot->connection, process_type, objname,
echo, verbose, concurrently, true, tablespace);
cell = cell->next;
} while (cell != NULL);
if (!ParallelSlotsWaitCompletion(sa))
failed = true;
finish:
if (process_list != user_list)
{
simple_string_list_destroy(process_list);
pg_free(process_list);
}
if (indices_tables_list)
{
simple_string_list_destroy(indices_tables_list);
pg_free(indices_tables_list);
}
ParallelSlotsTerminate(sa);
pfree(sa);
if (failed)
exit(1);
}
static void
run_reindex_command(PGconn *conn, ReindexType type, const char *name,
bool echo, bool verbose, bool concurrently, bool async,
const char *tablespace)
{
const char *paren = "(";
const char *comma = ", ";
const char *sep = paren;
PQExpBufferData sql;
bool status;
Assert(name);
/* build the REINDEX query */
initPQExpBuffer(&sql);
appendPQExpBufferStr(&sql, "REINDEX ");
if (verbose)
{
appendPQExpBuffer(&sql, "%sVERBOSE", sep);
sep = comma;
}
if (tablespace)
{
appendPQExpBuffer(&sql, "%sTABLESPACE %s", sep, fmtId(tablespace));
sep = comma;
}
if (sep != paren)
appendPQExpBufferStr(&sql, ") ");
/* object type */
switch (type)
{
case REINDEX_DATABASE:
appendPQExpBufferStr(&sql, "DATABASE ");
break;
case REINDEX_INDEX:
appendPQExpBufferStr(&sql, "INDEX ");
break;
case REINDEX_SCHEMA:
appendPQExpBufferStr(&sql, "SCHEMA ");
break;
case REINDEX_SYSTEM:
appendPQExpBufferStr(&sql, "SYSTEM ");
break;
case REINDEX_TABLE:
appendPQExpBufferStr(&sql, "TABLE ");
break;
}
/*
* Parenthesized grammar is only supported for CONCURRENTLY since
* PostgreSQL 14. Since 12, CONCURRENTLY can be specified after the
* object type.
*/
if (concurrently)
appendPQExpBufferStr(&sql, "CONCURRENTLY ");
/* object name */
switch (type)
{
case REINDEX_DATABASE:
case REINDEX_SYSTEM:
appendPQExpBufferStr(&sql, fmtId(name));
break;
case REINDEX_INDEX:
case REINDEX_TABLE:
appendQualifiedRelation(&sql, name, conn, echo);
break;
case REINDEX_SCHEMA:
appendPQExpBufferStr(&sql, name);
break;
}
/* finish the query */
appendPQExpBufferChar(&sql, ';');
if (async)
{
if (echo)
printf("%s\n", sql.data);
status = PQsendQuery(conn, sql.data) == 1;
}
else
status = executeMaintenanceCommand(conn, sql.data, echo);
if (!status)
{
switch (type)
{
case REINDEX_DATABASE:
pg_log_error("reindexing of database \"%s\" failed: %s",
PQdb(conn), PQerrorMessage(conn));
break;
case REINDEX_INDEX:
pg_log_error("reindexing of index \"%s\" in database \"%s\" failed: %s",
name, PQdb(conn), PQerrorMessage(conn));
break;
case REINDEX_SCHEMA:
pg_log_error("reindexing of schema \"%s\" in database \"%s\" failed: %s",
name, PQdb(conn), PQerrorMessage(conn));
break;
case REINDEX_SYSTEM:
pg_log_error("reindexing of system catalogs in database \"%s\" failed: %s",
PQdb(conn), PQerrorMessage(conn));
break;
case REINDEX_TABLE:
pg_log_error("reindexing of table \"%s\" in database \"%s\" failed: %s",
name, PQdb(conn), PQerrorMessage(conn));
break;
}
if (!async)
{
PQfinish(conn);
exit(1);
}
}
termPQExpBuffer(&sql);
}
/*
* Prepare the list of objects to process by querying the catalogs.
*
* This function will return a SimpleStringList object containing the entire
* list of tables in the given database that should be processed by a parallel
* database-wide reindex (excluding system tables), or NULL if there's no such
* table.
*/
static SimpleStringList *
get_parallel_object_list(PGconn *conn, ReindexType type,
SimpleStringList *user_list, bool echo)
{
PQExpBufferData catalog_query;
PQExpBufferData buf;
PGresult *res;
SimpleStringList *tables;
int ntups,
i;
initPQExpBuffer(&catalog_query);
/*
* The queries here are using a safe search_path, so there's no need to
* fully qualify everything.
*/
switch (type)
{
case REINDEX_DATABASE:
Assert(user_list == NULL);
appendPQExpBufferStr(&catalog_query,
"SELECT c.relname, ns.nspname\n"
" FROM pg_catalog.pg_class c\n"
" JOIN pg_catalog.pg_namespace ns"
" ON c.relnamespace = ns.oid\n"
" WHERE ns.nspname != 'pg_catalog'\n"
" AND c.relkind IN ("
CppAsString2(RELKIND_RELATION) ", "
CppAsString2(RELKIND_MATVIEW) ")\n"
" ORDER BY c.relpages DESC;");
break;
case REINDEX_SCHEMA:
{
SimpleStringListCell *cell;
bool nsp_listed = false;
Assert(user_list != NULL);
/*
* All the tables from all the listed schemas are grabbed at
* once.
*/
appendPQExpBufferStr(&catalog_query,
"SELECT c.relname, ns.nspname\n"
" FROM pg_catalog.pg_class c\n"
" JOIN pg_catalog.pg_namespace ns"
" ON c.relnamespace = ns.oid\n"
" WHERE c.relkind IN ("
CppAsString2(RELKIND_RELATION) ", "
CppAsString2(RELKIND_MATVIEW) ")\n"
" AND ns.nspname IN (");
for (cell = user_list->head; cell; cell = cell->next)
{
const char *nspname = cell->val;
if (nsp_listed)
appendPQExpBufferStr(&catalog_query, ", ");
else
nsp_listed = true;
appendStringLiteralConn(&catalog_query, nspname, conn);
}
appendPQExpBufferStr(&catalog_query, ")\n"
" ORDER BY c.relpages DESC;");
}
break;
case REINDEX_INDEX:
{
SimpleStringListCell *cell;
Assert(user_list != NULL);
/*
* Straight-forward index-level REINDEX is not supported with
* multiple jobs as we cannot control the concurrent
* processing of multiple indexes depending on the same
* relation. But we can extract the appropriate table name
* for the index and put REINDEX INDEX commands into different
* jobs, according to the parent tables.
*
* We will order the results to group the same tables
* together. We fetch index names as well to build a new list
* of them with matching order.
*/
appendPQExpBufferStr(&catalog_query,
"SELECT t.relname, n.nspname, i.relname\n"
"FROM pg_catalog.pg_index x\n"
"JOIN pg_catalog.pg_class t ON t.oid = x.indrelid\n"
"JOIN pg_catalog.pg_class i ON i.oid = x.indexrelid\n"
"LEFT JOIN pg_catalog.pg_namespace n ON n.oid = t.relnamespace\n"
"WHERE x.indexrelid OPERATOR(pg_catalog.=) ANY(ARRAY['");
for (cell = user_list->head; cell; cell = cell->next)
{
if (cell != user_list->head)
appendPQExpBufferStr(&catalog_query, "', '");
appendQualifiedRelation(&catalog_query, cell->val, conn, echo);
}
/*
* Order tables by the size of its greatest index. Within the
* table, order indexes by their sizes.
*/
appendPQExpBufferStr(&catalog_query,
"']::pg_catalog.regclass[])\n"
"ORDER BY max(i.relpages) OVER \n"
" (PARTITION BY n.nspname, t.relname),\n"
" n.nspname, t.relname, i.relpages;\n");
/*
* We're going to re-order the user_list to match the order of
* tables. So, empty the user_list to fill it from the query
* result.
*/
simple_string_list_destroy(user_list);
user_list->head = user_list->tail = NULL;
}
break;
case REINDEX_SYSTEM:
case REINDEX_TABLE:
Assert(false);
break;
}
res = executeQuery(conn, catalog_query.data, echo);
termPQExpBuffer(&catalog_query);
/*
* If no rows are returned, there are no matching tables, so we are done.
*/
ntups = PQntuples(res);
if (ntups == 0)
{
PQclear(res);
PQfinish(conn);
return NULL;
}
tables = pg_malloc0(sizeof(SimpleStringList));
/* Build qualified identifiers for each table */
initPQExpBuffer(&buf);
for (i = 0; i < ntups; i++)
{
appendPQExpBufferStr(&buf,
fmtQualifiedId(PQgetvalue(res, i, 1),
PQgetvalue(res, i, 0)));
simple_string_list_append(tables, buf.data);
resetPQExpBuffer(&buf);
if (type == REINDEX_INDEX)
{
/*
* For index-level REINDEX, rebuild the list of indexes to match
* the order of tables list.
*/
appendPQExpBufferStr(&buf,
fmtQualifiedId(PQgetvalue(res, i, 1),
PQgetvalue(res, i, 2)));
simple_string_list_append(user_list, buf.data);
resetPQExpBuffer(&buf);
}
}
termPQExpBuffer(&buf);
PQclear(res);
return tables;
}
static void
reindex_all_databases(ConnParams *cparams,
const char *progname, bool echo, bool quiet, bool verbose,
bool concurrently, int concurrentCons,
const char *tablespace, bool syscatalog,
SimpleStringList *schemas, SimpleStringList *tables,
SimpleStringList *indexes)
{
PGconn *conn;
PGresult *result;
int i;
conn = connectMaintenanceDatabase(cparams, progname, echo);
result = executeQuery(conn,
"SELECT datname FROM pg_database WHERE datallowconn AND datconnlimit <> -2 ORDER BY 1;",
echo);
PQfinish(conn);
for (i = 0; i < PQntuples(result); i++)
{
char *dbname = PQgetvalue(result, i, 0);
if (!quiet)
{
printf(_("%s: reindexing database \"%s\"\n"), progname, dbname);
fflush(stdout);
}
cparams->override_dbname = dbname;
if (syscatalog)
reindex_one_database(cparams, REINDEX_SYSTEM, NULL,
progname, echo, verbose,
concurrently, 1, tablespace);
if (schemas->head != NULL)
reindex_one_database(cparams, REINDEX_SCHEMA, schemas,
progname, echo, verbose,
concurrently, concurrentCons, tablespace);
if (indexes->head != NULL)
reindex_one_database(cparams, REINDEX_INDEX, indexes,
progname, echo, verbose,
concurrently, 1, tablespace);
if (tables->head != NULL)
reindex_one_database(cparams, REINDEX_TABLE, tables,
progname, echo, verbose,
concurrently, concurrentCons, tablespace);
/*
* reindex database only if neither index nor table nor schema nor
* system catalogs is specified
*/
if (!syscatalog && indexes->head == NULL &&
tables->head == NULL && schemas->head == NULL)
reindex_one_database(cparams, REINDEX_DATABASE, NULL,
progname, echo, verbose,
concurrently, concurrentCons, tablespace);
}
PQclear(result);
}
static void
help(const char *progname)
{
printf(_("%s reindexes a PostgreSQL database.\n\n"), progname);
printf(_("Usage:\n"));
printf(_(" %s [OPTION]... [DBNAME]\n"), progname);
printf(_("\nOptions:\n"));
printf(_(" -a, --all reindex all databases\n"));
printf(_(" --concurrently reindex concurrently\n"));
printf(_(" -d, --dbname=DBNAME database to reindex\n"));
printf(_(" -e, --echo show the commands being sent to the server\n"));
printf(_(" -i, --index=INDEX recreate specific index(es) only\n"));
printf(_(" -j, --jobs=NUM use this many concurrent connections to reindex\n"));
printf(_(" -q, --quiet don't write any messages\n"));
printf(_(" -s, --system reindex system catalogs only\n"));
printf(_(" -S, --schema=SCHEMA reindex specific schema(s) only\n"));
printf(_(" -t, --table=TABLE reindex specific table(s) only\n"));
printf(_(" --tablespace=TABLESPACE tablespace where indexes are rebuilt\n"));
printf(_(" -v, --verbose write a lot of output\n"));
printf(_(" -V, --version output version information, then exit\n"));
printf(_(" -?, --help show this help, then exit\n"));
printf(_("\nConnection options:\n"));
printf(_(" -h, --host=HOSTNAME database server host or socket directory\n"));
printf(_(" -p, --port=PORT database server port\n"));
printf(_(" -U, --username=USERNAME user name to connect as\n"));
printf(_(" -w, --no-password never prompt for password\n"));
printf(_(" -W, --password force password prompt\n"));
printf(_(" --maintenance-db=DBNAME alternate maintenance database\n"));
printf(_("\nRead the description of the SQL command REINDEX for details.\n"));
printf(_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
printf(_("%s home page: <%s>\n"), PACKAGE_NAME, PACKAGE_URL);
}
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