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Avoid unnecessary relation stats query in pg_dump.

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The few fields we need can be easily collected in getTables() and
getIndexes() and stored in RelStatsInfo.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Andres Freund <andres@anarazel.de>
Co-authored-by: Corey Huinker <corey.huinker@gmail.com>
Co-authored-by: Jeff Davis <pgsql@j-davis.com>
Discussion: https://postgr.es/m/CADkLM=f0a43aTd88xW4xCFayEF25g-7hTrHX_WhV40HyocsUGg@mail.gmail.com
This commit is contained in:
Jeff Davis
2025-02-25 19:49:49 -08:00
parent 6c349d83b6
commit 8f427187db
2 changed files with 64 additions and 86 deletions
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145
src/bin/pg_dump/pg_dump.c
View File

@ -56,6 +56,7 @@
#include "common/connect.h"
#include "common/int.h"
#include "common/relpath.h"
#include "common/shortest_dec.h"
#include "compress_io.h"
#include "dumputils.h"
#include "fe_utils/option_utils.h"
@ -524,6 +525,9 @@ main(int argc, char **argv)
pg_logging_set_level(PG_LOG_WARNING);
set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_dump"));
/* ensure that locale does not affect floating point interpretation */
setlocale(LC_NUMERIC, "C");
/*
* Initialize what we need for parallel execution, especially for thread
* support on Windows.
@ -6814,7 +6818,8 @@ getFuncs(Archive *fout)
*
*/
static RelStatsInfo *
getRelationStatistics(Archive *fout, DumpableObject *rel, char relkind)
getRelationStatistics(Archive *fout, DumpableObject *rel, int32 relpages,
float reltuples, int32 relallvisible, char relkind)
{
if (!fout->dopt->dumpStatistics)
return NULL;
@ -6839,6 +6844,9 @@ getRelationStatistics(Archive *fout, DumpableObject *rel, char relkind)
dobj->components |= DUMP_COMPONENT_STATISTICS;
dobj->name = pg_strdup(rel->name);
dobj->namespace = rel->namespace;
info->relpages = relpages;
info->reltuples = reltuples;
info->relallvisible = relallvisible;
info->relkind = relkind;
info->postponed_def = false;
@ -6874,6 +6882,8 @@ getTables(Archive *fout, int *numTables)
int i_relhasindex;
int i_relhasrules;
int i_relpages;
int i_reltuples;
int i_relallvisible;
int i_toastpages;
int i_owning_tab;
int i_owning_col;
@ -6924,7 +6934,7 @@ getTables(Archive *fout, int *numTables)
"c.relowner, "
"c.relchecks, "
"c.relhasindex, c.relhasrules, c.relpages, "
"c.relhastriggers, "
"c.reltuples, c.relallvisible, c.relhastriggers, "
"c.relpersistence, "
"c.reloftype, "
"c.relacl, "
@ -7088,6 +7098,8 @@ getTables(Archive *fout, int *numTables)
i_relhasindex = PQfnumber(res, "relhasindex");
i_relhasrules = PQfnumber(res, "relhasrules");
i_relpages = PQfnumber(res, "relpages");
i_reltuples = PQfnumber(res, "reltuples");
i_relallvisible = PQfnumber(res, "relallvisible");
i_toastpages = PQfnumber(res, "toastpages");
i_owning_tab = PQfnumber(res, "owning_tab");
i_owning_col = PQfnumber(res, "owning_col");
@ -7134,6 +7146,9 @@ getTables(Archive *fout, int *numTables)
for (i = 0; i < ntups; i++)
{
float reltuples = strtof(PQgetvalue(res, i, i_reltuples), NULL);
int32 relallvisible = atoi(PQgetvalue(res, i, i_relallvisible));
tblinfo[i].dobj.objType = DO_TABLE;
tblinfo[i].dobj.catId.tableoid = atooid(PQgetvalue(res, i, i_reltableoid));
tblinfo[i].dobj.catId.oid = atooid(PQgetvalue(res, i, i_reloid));
@ -7233,7 +7248,8 @@ getTables(Archive *fout, int *numTables)
/* Add statistics */
if (tblinfo[i].interesting)
getRelationStatistics(fout, &tblinfo[i].dobj, tblinfo[i].relkind);
getRelationStatistics(fout, &tblinfo[i].dobj, tblinfo[i].relpages,
reltuples, relallvisible, tblinfo[i].relkind);
/*
* Read-lock target tables to make sure they aren't DROPPED or altered
@ -7499,6 +7515,9 @@ getIndexes(Archive *fout, TableInfo tblinfo[], int numTables)
i_oid,
i_indrelid,
i_indexname,
i_relpages,
i_reltuples,
i_relallvisible,
i_parentidx,
i_indexdef,
i_indnkeyatts,
@ -7552,6 +7571,7 @@ getIndexes(Archive *fout, TableInfo tblinfo[], int numTables)
appendPQExpBufferStr(query,
"SELECT t.tableoid, t.oid, i.indrelid, "
"t.relname AS indexname, "
"t.relpages, t.reltuples, t.relallvisible, "
"pg_catalog.pg_get_indexdef(i.indexrelid) AS indexdef, "
"i.indkey, i.indisclustered, "
"c.contype, c.conname, "
@ -7659,6 +7679,9 @@ getIndexes(Archive *fout, TableInfo tblinfo[], int numTables)
i_oid = PQfnumber(res, "oid");
i_indrelid = PQfnumber(res, "indrelid");
i_indexname = PQfnumber(res, "indexname");
i_relpages = PQfnumber(res, "relpages");
i_reltuples = PQfnumber(res, "reltuples");
i_relallvisible = PQfnumber(res, "relallvisible");
i_parentidx = PQfnumber(res, "parentidx");
i_indexdef = PQfnumber(res, "indexdef");
i_indnkeyatts = PQfnumber(res, "indnkeyatts");
@ -7725,6 +7748,9 @@ getIndexes(Archive *fout, TableInfo tblinfo[], int numTables)
char contype;
char indexkind;
RelStatsInfo *relstats;
int32 relpages = atoi(PQgetvalue(res, j, i_relpages));
float reltuples = strtof(PQgetvalue(res, j, i_reltuples), NULL);
int32 relallvisible = atoi(PQgetvalue(res, j, i_relallvisible));
indxinfo[j].dobj.objType = DO_INDEX;
indxinfo[j].dobj.catId.tableoid = atooid(PQgetvalue(res, j, i_tableoid));
@ -7759,7 +7785,8 @@ getIndexes(Archive *fout, TableInfo tblinfo[], int numTables)
indexkind = RELKIND_PARTITIONED_INDEX;
contype = *(PQgetvalue(res, j, i_contype));
relstats = getRelationStatistics(fout, &indxinfo[j].dobj, indexkind);
relstats = getRelationStatistics(fout, &indxinfo[j].dobj, relpages,
reltuples, relallvisible, indexkind);
if (contype == 'p' || contype == 'u' || contype == 'x')
{
@ -10383,18 +10410,6 @@ dumpComment(Archive *fout, const char *type,
catalogId, subid, dumpId, NULL);
}
/*
* Tabular description of the parameters to pg_restore_relation_stats()
* param_name, param_type
*/
static const char *rel_stats_arginfo[][2] = {
{"relation", "regclass"},
{"version", "integer"},
{"relpages", "integer"},
{"reltuples", "real"},
{"relallvisible", "integer"},
};
/*
* Tabular description of the parameters to pg_restore_attribute_stats()
* param_name, param_type
@ -10419,30 +10434,6 @@ static const char *att_stats_arginfo[][2] = {
{"range_bounds_histogram", "text"},
};
/*
* getRelStatsExportQuery --
*
* Generate a query that will fetch all relation (e.g. pg_class)
* stats for a given relation.
*/
static void
getRelStatsExportQuery(PQExpBuffer query, Archive *fout,
const char *schemaname, const char *relname)
{
resetPQExpBuffer(query);
appendPQExpBufferStr(query,
"SELECT c.oid::regclass AS relation, "
"current_setting('server_version_num') AS version, "
"c.relpages, c.reltuples, c.relallvisible "
"FROM pg_class c "
"JOIN pg_namespace n "
"ON n.oid = c.relnamespace "
"WHERE n.nspname = ");
appendStringLiteralAH(query, schemaname, fout);
appendPQExpBufferStr(query, " AND c.relname = ");
appendStringLiteralAH(query, relname, fout);
}
/*
* getAttStatsExportQuery --
*
@ -10454,21 +10445,22 @@ getAttStatsExportQuery(PQExpBuffer query, Archive *fout,
const char *schemaname, const char *relname)
{
resetPQExpBuffer(query);
appendPQExpBufferStr(query,
"SELECT c.oid::regclass AS relation, "
"s.attname,"
"s.inherited,"
"current_setting('server_version_num') AS version, "
"s.null_frac,"
"s.avg_width,"
"s.n_distinct,"
"s.most_common_vals,"
"s.most_common_freqs,"
"s.histogram_bounds,"
"s.correlation,"
"s.most_common_elems,"
"s.most_common_elem_freqs,"
"s.elem_count_histogram,");
appendPQExpBuffer(query,
"SELECT c.oid::regclass AS relation, "
"s.attname,"
"s.inherited,"
"'%u'::integer AS version, "
"s.null_frac,"
"s.avg_width,"
"s.n_distinct,"
"s.most_common_vals,"
"s.most_common_freqs,"
"s.histogram_bounds,"
"s.correlation,"
"s.most_common_elems,"
"s.most_common_elem_freqs,"
"s.elem_count_histogram,",
fout->remoteVersion);
if (fout->remoteVersion >= 170000)
appendPQExpBufferStr(query,
@ -10521,34 +10513,21 @@ appendNamedArgument(PQExpBuffer out, Archive *fout, const char *argname,
* Append a formatted pg_restore_relation_stats statement.
*/
static void
appendRelStatsImport(PQExpBuffer out, Archive *fout, PGresult *res)
appendRelStatsImport(PQExpBuffer out, Archive *fout, const RelStatsInfo *rsinfo)
{
const char *sep = "";
const char *qualname = fmtQualifiedId(rsinfo->dobj.namespace->dobj.name, rsinfo->dobj.name);
char reltuples_str[FLOAT_SHORTEST_DECIMAL_LEN];
if (PQntuples(res) == 0)
return;
float_to_shortest_decimal_buf(rsinfo->reltuples, reltuples_str);
appendPQExpBufferStr(out, "SELECT * FROM pg_catalog.pg_restore_relation_stats(\n");
for (int argno = 0; argno < lengthof(rel_stats_arginfo); argno++)
{
const char *argname = rel_stats_arginfo[argno][0];
const char *argtype = rel_stats_arginfo[argno][1];
int fieldno = PQfnumber(res, argname);
if (fieldno < 0)
pg_fatal("relation stats export query missing field '%s'",
argname);
if (PQgetisnull(res, 0, fieldno))
continue;
appendPQExpBufferStr(out, sep);
appendNamedArgument(out, fout, argname, PQgetvalue(res, 0, fieldno), argtype);
sep = ",\n";
}
appendPQExpBufferStr(out, "\n);\n");
appendPQExpBuffer(out, "\t'relation', '%s'::regclass,\n", qualname);
appendPQExpBuffer(out, "\t'version', '%u'::integer,\n",
fout->remoteVersion);
appendPQExpBuffer(out, "\t'relpages', '%d'::integer,\n", rsinfo->relpages);
appendPQExpBuffer(out, "\t'reltuples', '%s'::real,\n", reltuples_str);
appendPQExpBuffer(out, "\t'relallvisible', '%d'::integer\n);\n",
rsinfo->relallvisible);
}
/*
@ -10643,15 +10622,11 @@ dumpRelationStats(Archive *fout, const RelStatsInfo *rsinfo)
tag = createPQExpBuffer();
appendPQExpBufferStr(tag, fmtId(dobj->name));
query = createPQExpBuffer();
out = createPQExpBuffer();
getRelStatsExportQuery(query, fout, dobj->namespace->dobj.name,
dobj->name);
res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
appendRelStatsImport(out, fout, res);
PQclear(res);
appendRelStatsImport(out, fout, rsinfo);
query = createPQExpBuffer();
getAttStatsExportQuery(query, fout, dobj->namespace->dobj.name,
dobj->name);
res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);

5
src/bin/pg_dump/pg_dump.h
View File

@ -328,7 +328,7 @@ typedef struct _tableInfo
Oid owning_tab; /* OID of table owning sequence */
int owning_col; /* attr # of column owning sequence */
bool is_identity_sequence;
int relpages; /* table's size in pages (from pg_class) */
int32 relpages; /* table's size in pages (from pg_class) */
int toastpages; /* toast table's size in pages, if any */
bool interesting; /* true if need to collect more data */
@ -438,6 +438,9 @@ typedef struct _indexAttachInfo
typedef struct _relStatsInfo
{
DumpableObject dobj;
int32 relpages;
float reltuples;
int32 relallvisible;
char relkind; /* 'r', 'm', 'i', etc */
bool postponed_def; /* stats must be postponed into post-data */
} RelStatsInfo;