diff options
Diffstat (limited to 'src/backend/commands/analyze.c')
| -rw-r--r-- | src/backend/commands/analyze.c | 59 |
1 files changed, 24 insertions, 35 deletions
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c index 0568a1bcf86..fa84989fc6f 100644 --- a/src/backend/commands/analyze.c +++ b/src/backend/commands/analyze.c @@ -84,8 +84,7 @@ static MemoryContext anl_context = NULL; static BufferAccessStrategy vac_strategy; -static void do_analyze_rel(Relation onerel, VacuumStmt *vacstmt, - bool update_reltuples, bool inh); +static void do_analyze_rel(Relation onerel, VacuumStmt *vacstmt, bool inh); static void BlockSampler_Init(BlockSampler bs, BlockNumber nblocks, int samplesize); static bool BlockSampler_HasMore(BlockSampler bs); @@ -115,18 +114,9 @@ static bool std_typanalyze(VacAttrStats *stats); /* * analyze_rel() -- analyze one relation - * - * If update_reltuples is true, we update reltuples and relpages columns - * in pg_class. Caller should pass false if we're part of VACUUM ANALYZE, - * and the VACUUM didn't skip any pages. We only have an approximate count, - * so we don't want to overwrite the accurate values already inserted by the - * VACUUM in that case. VACUUM always scans all indexes, however, so the - * pg_class entries for indexes are never updated if we're part of VACUUM - * ANALYZE. */ void -analyze_rel(Oid relid, VacuumStmt *vacstmt, - BufferAccessStrategy bstrategy, bool update_reltuples) +analyze_rel(Oid relid, VacuumStmt *vacstmt, BufferAccessStrategy bstrategy) { Relation onerel; @@ -238,13 +228,13 @@ analyze_rel(Oid relid, VacuumStmt *vacstmt, /* * Do the normal non-recursive ANALYZE. */ - do_analyze_rel(onerel, vacstmt, update_reltuples, false); + do_analyze_rel(onerel, vacstmt, false); /* * If there are child tables, do recursive ANALYZE. */ if (onerel->rd_rel->relhassubclass) - do_analyze_rel(onerel, vacstmt, false, true); + do_analyze_rel(onerel, vacstmt, true); /* * Close source relation now, but keep lock so that no one deletes it @@ -267,8 +257,7 @@ analyze_rel(Oid relid, VacuumStmt *vacstmt, * do_analyze_rel() -- analyze one relation, recursively or not */ static void -do_analyze_rel(Relation onerel, VacuumStmt *vacstmt, - bool update_reltuples, bool inh) +do_analyze_rel(Relation onerel, VacuumStmt *vacstmt, bool inh) { int attr_cnt, tcnt, @@ -437,9 +426,9 @@ do_analyze_rel(Relation onerel, VacuumStmt *vacstmt, } /* - * Quit if no analyzable columns and no pg_class update needed. + * Quit if no analyzable columns. */ - if (attr_cnt <= 0 && !analyzableindex && !update_reltuples) + if (attr_cnt <= 0 && !analyzableindex) goto cleanup; /* @@ -549,10 +538,10 @@ do_analyze_rel(Relation onerel, VacuumStmt *vacstmt, } /* - * Update pages/tuples stats in pg_class, but not if we're inside a VACUUM - * that got a more precise number. + * Update pages/tuples stats in pg_class ... but not if we're doing + * inherited stats. */ - if (update_reltuples) + if (!inh) vac_update_relstats(onerel, RelationGetNumberOfBlocks(onerel), totalrows, hasindex, InvalidTransactionId); @@ -562,7 +551,7 @@ do_analyze_rel(Relation onerel, VacuumStmt *vacstmt, * VACUUM ANALYZE, don't overwrite the accurate count already inserted by * VACUUM. */ - if (!(vacstmt->options & VACOPT_VACUUM)) + if (!inh && !(vacstmt->options & VACOPT_VACUUM)) { for (ind = 0; ind < nindexes; ind++) { @@ -577,13 +566,12 @@ do_analyze_rel(Relation onerel, VacuumStmt *vacstmt, } /* - * Report ANALYZE to the stats collector, too; likewise, tell it to adopt - * these numbers only if we're not inside a VACUUM that got a better - * number. However, a call with inh = true shouldn't reset the stats. + * Report ANALYZE to the stats collector, too. However, if doing + * inherited stats we shouldn't report, because the stats collector only + * tracks per-table stats. */ if (!inh) - pgstat_report_analyze(onerel, update_reltuples, - totalrows, totaldeadrows); + pgstat_report_analyze(onerel, totalrows, totaldeadrows); /* We skip to here if there were no analyzable columns */ cleanup: @@ -1243,18 +1231,19 @@ acquire_sample_rows(Relation onerel, HeapTuple *rows, int targrows, qsort((void *) rows, numrows, sizeof(HeapTuple), compare_rows); /* - * Estimate total numbers of rows in relation. + * Estimate total numbers of rows in relation. For live rows, use + * vac_estimate_reltuples; for dead rows, we have no source of old + * information, so we have to assume the density is the same in unseen + * pages as in the pages we scanned. */ + *totalrows = vac_estimate_reltuples(onerel, true, + totalblocks, + bs.m, + liverows); if (bs.m > 0) - { - *totalrows = floor((liverows * totalblocks) / bs.m + 0.5); - *totaldeadrows = floor((deadrows * totalblocks) / bs.m + 0.5); - } + *totaldeadrows = floor((deadrows / bs.m) * totalblocks + 0.5); else - { - *totalrows = 0.0; *totaldeadrows = 0.0; - } /* * Emit some interesting relation info |