@@ -209,6 +209,9 @@ static int nbinaryUpgradeClassOids = 0;
209209static SequenceItem *sequences = NULL;
210210static int nsequences = 0;
211211
212+ /* Maximum number of relations to fetch in a fetchAttributeStats() call. */
213+ #define MAX_ATTR_STATS_RELS 64
214+
212215/*
213216 * The default number of rows per INSERT when
214217 * --inserts is specified without --rows-per-insert
@@ -10553,6 +10556,78 @@ appendNamedArgument(PQExpBuffer out, Archive *fout, const char *argname,
1055310556 appendPQExpBuffer(out, "::%s", argtype);
1055410557}
1055510558
10559+ /*
10560+ * fetchAttributeStats --
10561+ *
10562+ * Fetch next batch of rows for getAttributeStats().
10563+ */
10564+ static PGresult *
10565+ fetchAttributeStats(Archive *fout)
10566+ {
10567+ ArchiveHandle *AH = (ArchiveHandle *) fout;
10568+ PQExpBuffer nspnames = createPQExpBuffer();
10569+ PQExpBuffer relnames = createPQExpBuffer();
10570+ int count = 0;
10571+ PGresult *res = NULL;
10572+ static TocEntry *te;
10573+ static bool restarted;
10574+
10575+ /* If we're just starting, set our TOC pointer. */
10576+ if (!te)
10577+ te = AH->toc->next;
10578+
10579+ /*
10580+ * We can't avoid a second TOC scan for the tar format because it writes
10581+ * restore.sql separately, which means we must execute all of our queries
10582+ * a second time. This feels risky, but there is no known reason it
10583+ * should generate different output than the first pass. Even if it does,
10584+ * the worst case is that restore.sql might have different statistics data
10585+ * than the archive.
10586+ */
10587+ if (!restarted && te == AH->toc && AH->format == archTar)
10588+ {
10589+ te = AH->toc->next;
10590+ restarted = true;
10591+ }
10592+
10593+ /*
10594+ * Scan the TOC for the next set of relevant stats entries. We assume
10595+ * that statistics are dumped in the order they are listed in the TOC.
10596+ * This is perhaps not the sturdiest assumption, so we verify it matches
10597+ * reality in dumpRelationStats_dumper().
10598+ */
10599+ for (; te != AH->toc && count < MAX_ATTR_STATS_RELS; te = te->next)
10600+ {
10601+ if (te->reqs && strcmp(te->desc, "STATISTICS DATA") == 0)
10602+ {
10603+ RelStatsInfo *rsinfo = (RelStatsInfo *) te->defnDumperArg;
10604+
10605+ appendPQExpBuffer(nspnames, "%s%s", count ? "," : "",
10606+ fmtId(rsinfo->dobj.namespace->dobj.name));
10607+ appendPQExpBuffer(relnames, "%s%s", count ? "," : "",
10608+ fmtId(rsinfo->dobj.name));
10609+ count++;
10610+ }
10611+ }
10612+
10613+ /* Execute the query for the next batch of relations. */
10614+ if (count > 0)
10615+ {
10616+ PQExpBuffer query = createPQExpBuffer();
10617+
10618+ appendPQExpBuffer(query, "EXECUTE getAttributeStats("
10619+ "'{%s}'::pg_catalog.name[],"
10620+ "'{%s}'::pg_catalog.name[])",
10621+ nspnames->data, relnames->data);
10622+ res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
10623+ destroyPQExpBuffer(query);
10624+ }
10625+
10626+ destroyPQExpBuffer(nspnames);
10627+ destroyPQExpBuffer(relnames);
10628+ return res;
10629+ }
10630+
1055610631/*
1055710632 * dumpRelationStats_dumper --
1055810633 *
@@ -10561,14 +10636,17 @@ appendNamedArgument(PQExpBuffer out, Archive *fout, const char *argname,
1056110636 * dumped.
1056210637 */
1056310638static char *
10564- dumpRelationStats_dumper(Archive *fout, const void *userArg)
10639+ dumpRelationStats_dumper(Archive *fout, const void *userArg, const TocEntry *te )
1056510640{
1056610641 const RelStatsInfo *rsinfo = (RelStatsInfo *) userArg;
1056710642 const DumpableObject *dobj = &rsinfo->dobj;
10568- PGresult *res;
10643+ static PGresult *res;
10644+ static int rownum;
1056910645 PQExpBuffer query;
1057010646 PQExpBufferData out_data;
1057110647 PQExpBuffer out = &out_data;
10648+ int i_schemaname;
10649+ int i_tablename;
1057210650 int i_attname;
1057310651 int i_inherited;
1057410652 int i_null_frac;
@@ -10584,13 +10662,30 @@ dumpRelationStats_dumper(Archive *fout, const void *userArg)
1058410662 int i_range_length_histogram;
1058510663 int i_range_empty_frac;
1058610664 int i_range_bounds_histogram;
10665+ static TocEntry *next_te;
10666+
10667+ /*
10668+ * fetchAttributeStats() assumes that the statistics are dumped in the
10669+ * order they are listed in the TOC. We verify that here for safety.
10670+ */
10671+ if (!next_te)
10672+ next_te = ((ArchiveHandle *) fout)->toc;
10673+
10674+ next_te = next_te->next;
10675+ while (!next_te->reqs || strcmp(next_te->desc, "STATISTICS DATA") != 0)
10676+ next_te = next_te->next;
10677+
10678+ if (te != next_te)
10679+ pg_fatal("stats dumped out of order (current: %d %s %s) (expected: %d %s %s)",
10680+ te->dumpId, te->desc, te->tag,
10681+ next_te->dumpId, next_te->desc, next_te->tag);
1058710682
1058810683 query = createPQExpBuffer();
1058910684 if (!fout->is_prepared[PREPQUERY_GETATTRIBUTESTATS])
1059010685 {
1059110686 appendPQExpBufferStr(query,
10592- "PREPARE getAttributeStats(pg_catalog.name, pg_catalog.name) AS\n"
10593- "SELECT s.attname, s.inherited, "
10687+ "PREPARE getAttributeStats(pg_catalog.name[] , pg_catalog.name[] ) AS\n"
10688+ "SELECT s.schemaname, s.tablename, s. attname, s.inherited, "
1059410689 "s.null_frac, s.avg_width, s.n_distinct, "
1059510690 "s.most_common_vals, s.most_common_freqs, "
1059610691 "s.histogram_bounds, s.correlation, "
@@ -10608,11 +10703,21 @@ dumpRelationStats_dumper(Archive *fout, const void *userArg)
1060810703 "NULL AS range_empty_frac,"
1060910704 "NULL AS range_bounds_histogram ");
1061010705
10706+ /*
10707+ * The results must be in the order of the relations supplied in the
10708+ * parameters to ensure we remain in sync as we walk through the TOC.
10709+ * The redundant filter clause on s.tablename = ANY(...) seems
10710+ * sufficient to convince the planner to use the
10711+ * pg_class_relname_nsp_index, which avoids an full scan of pg_stats.
10712+ * This may not work for all versions.
10713+ */
1061110714 appendPQExpBufferStr(query,
1061210715 "FROM pg_catalog.pg_stats s "
10613- "WHERE s.schemaname = $1 "
10614- "AND s.tablename = $2 "
10615- "ORDER BY s.attname, s.inherited");
10716+ "JOIN unnest($1, $2) WITH ORDINALITY AS u (schemaname, tablename, ord) "
10717+ "ON s.schemaname = u.schemaname "
10718+ "AND s.tablename = u.tablename "
10719+ "WHERE s.tablename = ANY($2) "
10720+ "ORDER BY u.ord, s.attname, s.inherited");
1061610721
1061710722 ExecuteSqlStatement(fout, query->data);
1061810723
@@ -10642,16 +10747,16 @@ dumpRelationStats_dumper(Archive *fout, const void *userArg)
1064210747
1064310748 appendPQExpBufferStr(out, "\n);\n");
1064410749
10750+ /* Fetch the next batch of attribute statistics if needed. */
10751+ if (rownum >= PQntuples(res))
10752+ {
10753+ PQclear(res);
10754+ res = fetchAttributeStats(fout);
10755+ rownum = 0;
10756+ }
1064510757
10646- /* fetch attribute stats */
10647- appendPQExpBufferStr(query, "EXECUTE getAttributeStats(");
10648- appendStringLiteralAH(query, dobj->namespace->dobj.name, fout);
10649- appendPQExpBufferStr(query, ", ");
10650- appendStringLiteralAH(query, dobj->name, fout);
10651- appendPQExpBufferStr(query, ");");
10652-
10653- res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
10654-
10758+ i_schemaname = PQfnumber(res, "schemaname");
10759+ i_tablename = PQfnumber(res, "tablename");
1065510760 i_attname = PQfnumber(res, "attname");
1065610761 i_inherited = PQfnumber(res, "inherited");
1065710762 i_null_frac = PQfnumber(res, "null_frac");
@@ -10669,10 +10774,15 @@ dumpRelationStats_dumper(Archive *fout, const void *userArg)
1066910774 i_range_bounds_histogram = PQfnumber(res, "range_bounds_histogram");
1067010775
1067110776 /* restore attribute stats */
10672- for (int rownum = 0 ; rownum < PQntuples(res); rownum++)
10777+ for (; rownum < PQntuples(res); rownum++)
1067310778 {
1067410779 const char *attname;
1067510780
10781+ /* Stop if the next stat row in our cache isn't for this relation. */
10782+ if (strcmp(dobj->name, PQgetvalue(res, rownum, i_tablename)) != 0 ||
10783+ strcmp(dobj->namespace->dobj.name, PQgetvalue(res, rownum, i_schemaname)) != 0)
10784+ break;
10785+
1067610786 appendPQExpBufferStr(out, "SELECT * FROM pg_catalog.pg_restore_attribute_stats(\n");
1067710787 appendPQExpBuffer(out, "\t'version', '%u'::integer,\n",
1067810788 fout->remoteVersion);
@@ -10762,8 +10872,6 @@ dumpRelationStats_dumper(Archive *fout, const void *userArg)
1076210872 appendPQExpBufferStr(out, "\n);\n");
1076310873 }
1076410874
10765- PQclear(res);
10766-
1076710875 destroyPQExpBuffer(query);
1076810876 return out->data;
1076910877}
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