*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.151 2000/05/29 01:55:07 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.152 2000/05/29 15:44:55 momjian Exp $
*
*-------------------------------------------------------------------------
static void vac_vacuum(NameData *VacRelP, bool analyze, List *va_cols);
static VRelList getrels(NameData *VacRelP);
static void vacuum_rel(Oid relid, bool analyze, List *va_cols);
+static void analyze_rel(Oid relid, List *va_cols);
static void scan_heap(VRelStats *vacrelstats, Relation onerel, VPageList vacuum_pages, VPageList fraged_pages);
static void repair_frag(VRelStats *vacrelstats, Relation onerel, VPageList vacuum_pages, VPageList fraged_pages, int nindices, Relation *Irel);
static void vacuum_heap(VRelStats *vacrelstats, Relation onerel, VPageList vpl);
static void vacuum_page(Page page, VPageDescr vpd);
static void vacuum_index(VPageList vpl, Relation indrel, int num_tuples, int keep_tuples);
static void scan_index(Relation indrel, int num_tuples);
-static void attr_stats(Relation onerel, VRelStats *vacrelstats, HeapTuple tuple);
+static void attr_stats(Relation onerel, int attr_cnt, VacAttrStats *vacattrstats, HeapTuple tuple);
static void bucketcpy(Form_pg_attribute attr, Datum value, Datum *bucket, int *bucket_len);
-static void update_stats(Oid relid, int num_pages, int num_tuples, bool hasindex, VRelStats *vacrelstats);
+static void update_relstats(Oid relid, int num_pages, int num_tuples, bool hasindex, VRelStats *vacrelstats);
+static void update_attstats(Oid relid, int natts, VacAttrStats *vacattrstats);
static void del_stats(Oid relid, int attcnt, int *attnums);
static VPageDescr tid_reaped(ItemPointer itemptr, VPageList vpl);
static void reap_page(VPageList vpl, VPageDescr vpc);
static int vac_cmp_vtlinks(const void *left, const void *right);
static bool enough_space(VPageDescr vpd, Size len);
static char *show_rusage(struct rusage * ru0);
-
-
-/*
- * This routines handle a special cross-transaction portal.
- * However it is automatically closed in case of abort.
- */
-void
-CommonSpecialPortalOpen(void)
-{
- char *pname;
-
-
- if (CommonSpecialPortalInUse)
- elog(ERROR, "CommonSpecialPortal is in use");
-
- /*
- * Create a portal for safe memory across transactions. We need to
- * palloc the name space for it because our hash function expects the
- * name to be on a longword boundary. CreatePortal copies the name to
- * safe storage for us.
- */
- pname = pstrdup(VACPNAME);
- vac_portal = CreatePortal(pname);
- pfree(pname);
-
- /*
- * Set flag to indicate that vac_portal must be removed after an error.
- * This global variable is checked in the transaction manager on xact
- * abort, and the routine CommonSpecialPortalClose() is called if
- * necessary.
- */
- CommonSpecialPortalInUse = true;
-}
-
-void
-CommonSpecialPortalClose(void)
-{
- /* Clear flag first, to avoid recursion if PortalDrop elog's */
- CommonSpecialPortalInUse = false;
-
- /*
- * Release our portal for cross-transaction memory.
- */
- PortalDrop(&vac_portal);
-}
-
-PortalVariableMemory
-CommonSpecialPortalGetMemory(void)
-{
- return PortalGetVariableMemory(vac_portal);
-}
-
-bool
-CommonSpecialPortalIsOpen(void)
-{
- return CommonSpecialPortalInUse;
-}
+/* CommonSpecialPortal function at the bottom */
void
vacuum(char *vacrel, bool verbose, bool analyze, List *va_spec)
/* vacuum each heap relation */
for (cur = vrl; cur != (VRelList) NULL; cur = cur->vrl_next)
vacuum_rel(cur->vrl_relid, analyze, va_cols);
+
+ /* analyze separately so locking is minimized */
+ if (analyze)
+ for (cur = vrl; cur != (VRelList) NULL; cur = cur->vrl_next)
+ analyze_rel(cur->vrl_relid, va_cols);
}
static VRelList
static void
vacuum_rel(Oid relid, bool analyze, List *va_cols)
{
- HeapTuple tuple,
- typetuple;
+ HeapTuple tuple;
Relation onerel;
VPageListData vacuum_pages; /* List of pages to vacuum and/or clean
* indices */
vacrelstats->num_pages = vacrelstats->num_tuples = 0;
vacrelstats->hasindex = false;
- /*
- * we can VACUUM ANALYZE any table except pg_statistic; see
- * update_stats
- */
- if (analyze &&
- strcmp(RelationGetRelationName(onerel), StatisticRelationName) != 0)
- {
- int attr_cnt,
- *attnums = NULL;
- Form_pg_attribute *attr;
-
- attr_cnt = onerel->rd_att->natts;
- attr = onerel->rd_att->attrs;
-
- if (va_cols != NIL)
- {
- int tcnt = 0;
- List *le;
-
- if (length(va_cols) > attr_cnt)
- elog(ERROR, "vacuum: too many attributes specified for relation %s",
- RelationGetRelationName(onerel));
- attnums = (int *) palloc(attr_cnt * sizeof(int));
- foreach(le, va_cols)
- {
- char *col = (char *) lfirst(le);
-
- for (i = 0; i < attr_cnt; i++)
- {
- if (namestrcmp(&(attr[i]->attname), col) == 0)
- break;
- }
- if (i < attr_cnt) /* found */
- attnums[tcnt++] = i;
- else
- {
- elog(ERROR, "vacuum: there is no attribute %s in %s",
- col, RelationGetRelationName(onerel));
- }
- }
- attr_cnt = tcnt;
- }
-
- vacrelstats->vacattrstats = (VacAttrStats *) palloc(attr_cnt * sizeof(VacAttrStats));
-
- for (i = 0; i < attr_cnt; i++)
- {
- Operator func_operator;
- Form_pg_operator pgopform;
- VacAttrStats *stats;
-
- stats = &vacrelstats->vacattrstats[i];
- stats->attr = palloc(ATTRIBUTE_TUPLE_SIZE);
- memmove(stats->attr, attr[((attnums) ? attnums[i] : i)], ATTRIBUTE_TUPLE_SIZE);
- stats->best = stats->guess1 = stats->guess2 = 0;
- stats->max = stats->min = 0;
- stats->best_len = stats->guess1_len = stats->guess2_len = 0;
- stats->max_len = stats->min_len = 0;
- stats->initialized = false;
- stats->best_cnt = stats->guess1_cnt = stats->guess1_hits = stats->guess2_hits = 0;
- stats->max_cnt = stats->min_cnt = stats->null_cnt = stats->nonnull_cnt = 0;
-
- func_operator = oper("=", stats->attr->atttypid, stats->attr->atttypid, true);
- if (func_operator != NULL)
- {
- pgopform = (Form_pg_operator) GETSTRUCT(func_operator);
- fmgr_info(pgopform->oprcode, &(stats->f_cmpeq));
- }
- else
- stats->f_cmpeq.fn_addr = NULL;
-
- func_operator = oper("<", stats->attr->atttypid, stats->attr->atttypid, true);
- if (func_operator != NULL)
- {
- pgopform = (Form_pg_operator) GETSTRUCT(func_operator);
- fmgr_info(pgopform->oprcode, &(stats->f_cmplt));
- stats->op_cmplt = oprid(func_operator);
- }
- else
- {
- stats->f_cmplt.fn_addr = NULL;
- stats->op_cmplt = InvalidOid;
- }
-
- func_operator = oper(">", stats->attr->atttypid, stats->attr->atttypid, true);
- if (func_operator != NULL)
- {
- pgopform = (Form_pg_operator) GETSTRUCT(func_operator);
- fmgr_info(pgopform->oprcode, &(stats->f_cmpgt));
- }
- else
- stats->f_cmpgt.fn_addr = NULL;
-
- typetuple = SearchSysCacheTuple(TYPEOID,
- ObjectIdGetDatum(stats->attr->atttypid),
- 0, 0, 0);
- if (HeapTupleIsValid(typetuple))
- {
- stats->outfunc = ((Form_pg_type) GETSTRUCT(typetuple))->typoutput;
- stats->typelem = ((Form_pg_type) GETSTRUCT(typetuple))->typelem;
- }
- else
- {
- stats->outfunc = InvalidOid;
- stats->typelem = InvalidOid;
- }
- }
- vacrelstats->va_natts = attr_cnt;
- /* delete existing pg_statistic rows for relation */
- del_stats(relid, ((attnums) ? attr_cnt : 0), attnums);
- if (attnums)
- pfree(attnums);
- }
- else
- {
- vacrelstats->va_natts = 0;
- vacrelstats->vacattrstats = (VacAttrStats *) NULL;
- }
-
GetXmaxRecent(&XmaxRecent);
/* scan it */
vacuum_index(&vacuum_pages, Irel[i], vacrelstats->num_tuples, 0);
}
else
-/* just scan indices to update statistic */
+ /* just scan indices to update statistic */
{
for (i = 0; i < nindices; i++)
scan_index(Irel[i], vacrelstats->num_tuples);
pfree(fraged_pages.vpl_pagedesc);
}
- /* update statistics in pg_class */
- update_stats(vacrelstats->relid, vacrelstats->num_pages,
- vacrelstats->num_tuples, vacrelstats->hasindex, vacrelstats);
-
/* all done with this class, but hold lock until commit */
heap_close(onerel, NoLock);
+ /* update statistics in pg_class */
+ update_relstats(vacrelstats->relid, vacrelstats->num_pages,
+ vacrelstats->num_tuples, vacrelstats->hasindex, vacrelstats);
+
/* next command frees attribute stats */
CommitTransactionCommand();
}
/*
+ * analyze_rel() -- analyze relation
+ */
+static void
+analyze_rel(Oid relid, List *va_cols)
+{
+ HeapTuple tuple,
+ typetuple;
+ Relation onerel;
+ int32 i;
+ int attr_cnt,
+ *attnums = NULL;
+ Form_pg_attribute *attr;
+ VacAttrStats *vacattrstats;
+ HeapScanDesc scan;
+
+ StartTransactionCommand();
+
+ /*
+ * Check for user-requested abort. Note we want this to be inside a
+ * transaction, so xact.c doesn't issue useless NOTICE.
+ */
+ if (QueryCancel)
+ CancelQuery();
+
+ /*
+ * Race condition -- if the pg_class tuple has gone away since the
+ * last time we saw it, we don't need to vacuum it.
+ */
+ tuple = SearchSysCacheTuple(RELOID,
+ ObjectIdGetDatum(relid),
+ 0, 0, 0);
+ /*
+ * We can VACUUM ANALYZE any table except pg_statistic.
+ * see update_relstats
+ */
+ if (!HeapTupleIsValid(tuple) ||
+ strcmp(NameStr(((Form_pg_class) GETSTRUCT(tuple))->relname),
+ StatisticRelationName) == 0)
+ {
+ CommitTransactionCommand();
+ return;
+ }
+
+ /*
+ * Open the class, get an exclusive lock on it, and check permissions.
+ *
+ * Note we choose to treat permissions failure as a NOTICE and keep
+ * trying to vacuum the rest of the DB --- is this appropriate?
+ */
+ onerel = heap_open(relid, AccessShareLock);
+
+#ifndef NO_SECURITY
+ if (!pg_ownercheck(GetPgUserName(), RelationGetRelationName(onerel),
+ RELNAME))
+ {
+ /* we already did an elog during vacuum
+ elog(NOTICE, "Skipping \"%s\" --- only table owner can VACUUM it",
+ RelationGetRelationName(onerel));
+ */
+ heap_close(onerel, AccessExclusiveLock);
+ CommitTransactionCommand();
+ return;
+ }
+#endif
+
+ attr_cnt = onerel->rd_att->natts;
+ attr = onerel->rd_att->attrs;
+
+ if (va_cols != NIL)
+ {
+ int tcnt = 0;
+ List *le;
+
+ if (length(va_cols) > attr_cnt)
+ elog(ERROR, "vacuum: too many attributes specified for relation %s",
+ RelationGetRelationName(onerel));
+ attnums = (int *) palloc(attr_cnt * sizeof(int));
+ foreach(le, va_cols)
+ {
+ char *col = (char *) lfirst(le);
+
+ for (i = 0; i < attr_cnt; i++)
+ {
+ if (namestrcmp(&(attr[i]->attname), col) == 0)
+ break;
+ }
+ if (i < attr_cnt) /* found */
+ attnums[tcnt++] = i;
+ else
+ {
+ elog(ERROR, "vacuum: there is no attribute %s in %s",
+ col, RelationGetRelationName(onerel));
+ }
+ }
+ attr_cnt = tcnt;
+ }
+
+ vacattrstats = (VacAttrStats *) palloc(attr_cnt * sizeof(VacAttrStats));
+
+ for (i = 0; i < attr_cnt; i++)
+ {
+ Operator func_operator;
+ Form_pg_operator pgopform;
+ VacAttrStats *stats;
+
+ stats = &vacattrstats[i];
+ stats->attr = palloc(ATTRIBUTE_TUPLE_SIZE);
+ memmove(stats->attr, attr[((attnums) ? attnums[i] : i)], ATTRIBUTE_TUPLE_SIZE);
+ stats->best = stats->guess1 = stats->guess2 = 0;
+ stats->max = stats->min = 0;
+ stats->best_len = stats->guess1_len = stats->guess2_len = 0;
+ stats->max_len = stats->min_len = 0;
+ stats->initialized = false;
+ stats->best_cnt = stats->guess1_cnt = stats->guess1_hits = stats->guess2_hits = 0;
+ stats->max_cnt = stats->min_cnt = stats->null_cnt = stats->nonnull_cnt = 0;
+
+ func_operator = oper("=", stats->attr->atttypid, stats->attr->atttypid, true);
+ if (func_operator != NULL)
+ {
+ pgopform = (Form_pg_operator) GETSTRUCT(func_operator);
+ fmgr_info(pgopform->oprcode, &(stats->f_cmpeq));
+ }
+ else
+ stats->f_cmpeq.fn_addr = NULL;
+
+ func_operator = oper("<", stats->attr->atttypid, stats->attr->atttypid, true);
+ if (func_operator != NULL)
+ {
+ pgopform = (Form_pg_operator) GETSTRUCT(func_operator);
+ fmgr_info(pgopform->oprcode, &(stats->f_cmplt));
+ stats->op_cmplt = oprid(func_operator);
+ }
+ else
+ {
+ stats->f_cmplt.fn_addr = NULL;
+ stats->op_cmplt = InvalidOid;
+ }
+
+ func_operator = oper(">", stats->attr->atttypid, stats->attr->atttypid, true);
+ if (func_operator != NULL)
+ {
+ pgopform = (Form_pg_operator) GETSTRUCT(func_operator);
+ fmgr_info(pgopform->oprcode, &(stats->f_cmpgt));
+ }
+ else
+ stats->f_cmpgt.fn_addr = NULL;
+
+ typetuple = SearchSysCacheTuple(TYPEOID,
+ ObjectIdGetDatum(stats->attr->atttypid),
+ 0, 0, 0);
+ if (HeapTupleIsValid(typetuple))
+ {
+ stats->outfunc = ((Form_pg_type) GETSTRUCT(typetuple))->typoutput;
+ stats->typelem = ((Form_pg_type) GETSTRUCT(typetuple))->typelem;
+ }
+ else
+ {
+ stats->outfunc = InvalidOid;
+ stats->typelem = InvalidOid;
+ }
+ }
+ /* delete existing pg_statistic rows for relation */
+ del_stats(relid, ((attnums) ? attr_cnt : 0), attnums);
+
+ scan = heap_beginscan(onerel, false, SnapshotNow, 0, NULL);
+
+ while (HeapTupleIsValid(tuple = heap_getnext(scan, 0)))
+ attr_stats(onerel, attr_cnt, vacattrstats, tuple);
+
+ heap_endscan(scan);
+
+ heap_close(onerel, AccessShareLock);
+
+ /* update statistics in pg_class */
+ update_attstats(relid, attr_cnt, vacattrstats);
+
+ CommitTransactionCommand();
+}
+
+/*
* scan_heap() -- scan an open heap relation
*
* This routine sets commit times, constructs vacuum_pages list of
min_tlen = tuple.t_len;
if (tuple.t_len > max_tlen)
max_tlen = tuple.t_len;
- attr_stats(onerel, vacrelstats, &tuple);
}
}
/* now update statistics in pg_class */
nipages = RelationGetNumberOfBlocks(indrel);
- update_stats(RelationGetRelid(indrel), nipages, nitups, false, NULL);
+ update_relstats(RelationGetRelid(indrel), nipages, nitups, false, NULL);
elog(MESSAGE_LEVEL, "Index %s: Pages %u; Tuples %u. %s",
RelationGetRelationName(indrel), nipages, nitups,
/* now update statistics in pg_class */
num_pages = RelationGetNumberOfBlocks(indrel);
- update_stats(RelationGetRelid(indrel), num_pages, num_index_tuples, false, NULL);
+ update_relstats(RelationGetRelid(indrel), num_pages, num_index_tuples, false, NULL);
elog(MESSAGE_LEVEL, "Index %s: Pages %u; Tuples %u: Deleted %u. %s",
RelationGetRelationName(indrel), num_pages,
*
*/
static void
-attr_stats(Relation onerel, VRelStats *vacrelstats, HeapTuple tuple)
+attr_stats(Relation onerel, int attr_cnt, VacAttrStats *vacattrstats, HeapTuple tuple)
{
- int i,
- attr_cnt = vacrelstats->va_natts;
- VacAttrStats *vacattrstats = vacrelstats->vacattrstats;
+ int i;
TupleDesc tupDesc = onerel->rd_att;
Datum value;
bool isnull;
}
/*
- * update_stats() -- update statistics for one relation
+ * update_relstats() -- update statistics for one relation
*
* Statistics are stored in several places: the pg_class row for the
* relation has stats about the whole relation, the pg_attribute rows
* Updating pg_class's own statistics would be especially tricky.
* Of course, this only works for fixed-size never-null columns, but
* these are.
- *
- * Updates of pg_attribute statistics are handled in the same way
- * for the same reasons.
- *
- * To keep things simple, we punt for pg_statistic, and don't try
- * to compute or store rows for pg_statistic itself in pg_statistic.
- * This could possibly be made to work, but it's not worth the trouble.
*/
static void
-update_stats(Oid relid, int num_pages, int num_tuples, bool hasindex,
+update_relstats(Oid relid, int num_pages, int num_tuples, bool hasindex,
VRelStats *vacrelstats)
{
- Relation rd,
- ad,
- sd;
- HeapScanDesc scan;
+ Relation rd;
HeapTupleData rtup;
- HeapTuple ctup,
- atup,
- stup;
+ HeapTuple ctup;
Form_pg_class pgcform;
- ScanKeyData askey;
- Form_pg_attribute attp;
Buffer buffer;
/*
WriteBuffer(buffer);
heap_close(rd, RowExclusiveLock);
+}
- if (vacrelstats != NULL && vacrelstats->va_natts > 0)
- {
- VacAttrStats *vacattrstats = vacrelstats->vacattrstats;
- int natts = vacrelstats->va_natts;
+/*
+ * update_attstats() -- update attribute statistics for one relation
+ *
+ * Updates of pg_attribute statistics are handled by over-write.
+ * for reasons described above.
+ *
+ * To keep things simple, we punt for pg_statistic, and don't try
+ * to compute or store rows for pg_statistic itself in pg_statistic.
+ * This could possibly be made to work, but it's not worth the trouble.
+ */
+static void
+update_attstats(Oid relid, int natts, VacAttrStats *vacattrstats)
+{
+ Relation ad,
+ sd;
+ HeapScanDesc scan;
+ HeapTuple atup,
+ stup;
+ ScanKeyData askey;
+ Form_pg_attribute attp;
- ad = heap_openr(AttributeRelationName, RowExclusiveLock);
- sd = heap_openr(StatisticRelationName, RowExclusiveLock);
+ ad = heap_openr(AttributeRelationName, RowExclusiveLock);
+ sd = heap_openr(StatisticRelationName, RowExclusiveLock);
- /* Find pg_attribute rows for this relation */
- ScanKeyEntryInitialize(&askey, 0, Anum_pg_attribute_attrelid,
- F_INT4EQ, relid);
+ /* Find pg_attribute rows for this relation */
+ ScanKeyEntryInitialize(&askey, 0, Anum_pg_attribute_attrelid,
+ F_INT4EQ, relid);
- scan = heap_beginscan(ad, false, SnapshotNow, 1, &askey);
+ scan = heap_beginscan(ad, false, SnapshotNow, 1, &askey);
- while (HeapTupleIsValid(atup = heap_getnext(scan, 0)))
+ while (HeapTupleIsValid(atup = heap_getnext(scan, 0)))
+ {
+ int i;
+ VacAttrStats *stats;
+
+ attp = (Form_pg_attribute) GETSTRUCT(atup);
+ if (attp->attnum <= 0) /* skip system attributes for now */
+ continue;
+
+ for (i = 0; i < natts; i++)
{
- int i;
- VacAttrStats *stats;
+ if (attp->attnum == vacattrstats[i].attr->attnum)
+ break;
+ }
+ if (i >= natts)
+ continue; /* skip attr if no stats collected */
+ stats = &(vacattrstats[i]);
- attp = (Form_pg_attribute) GETSTRUCT(atup);
- if (attp->attnum <= 0) /* skip system attributes for now */
- continue;
+ if (VacAttrStatsEqValid(stats))
+ {
+ float32data selratio; /* average ratio of rows selected
+ * for a random constant */
- for (i = 0; i < natts; i++)
+ /* Compute disbursion */
+ if (stats->nonnull_cnt == 0 && stats->null_cnt == 0)
{
- if (attp->attnum == vacattrstats[i].attr->attnum)
- break;
- }
- if (i >= natts)
- continue; /* skip attr if no stats collected */
- stats = &(vacattrstats[i]);
- if (VacAttrStatsEqValid(stats))
+ /*
+ * empty relation, so put a dummy value in
+ * attdisbursion
+ */
+ selratio = 0;
+ }
+ else if (stats->null_cnt <= 1 && stats->best_cnt == 1)
{
- float32data selratio; /* average ratio of rows selected
- * for a random constant */
-
- /* Compute disbursion */
- if (stats->nonnull_cnt == 0 && stats->null_cnt == 0)
+ /*
+ * looks like we have a unique-key attribute --- flag
+ * this with special -1.0 flag value.
+ *
+ * The correct disbursion is 1.0/numberOfRows, but since
+ * the relation row count can get updated without
+ * recomputing disbursion, we want to store a
+ * "symbolic" value and figure 1.0/numberOfRows on the
+ * fly.
+ */
+ selratio = -1;
+ }
+ else
+ {
+ if (VacAttrStatsLtGtValid(stats) &&
+ stats->min_cnt + stats->max_cnt == stats->nonnull_cnt)
{
/*
- * empty relation, so put a dummy value in
- * attdisbursion
+ * exact result when there are just 1 or 2
+ * values...
*/
- selratio = 0;
- }
- else if (stats->null_cnt <= 1 && stats->best_cnt == 1)
- {
+ double min_cnt_d = stats->min_cnt,
+ max_cnt_d = stats->max_cnt,
+ null_cnt_d = stats->null_cnt;
+ double total = ((double) stats->nonnull_cnt) + null_cnt_d;
- /*
- * looks like we have a unique-key attribute --- flag
- * this with special -1.0 flag value.
- *
- * The correct disbursion is 1.0/numberOfRows, but since
- * the relation row count can get updated without
- * recomputing disbursion, we want to store a
- * "symbolic" value and figure 1.0/numberOfRows on the
- * fly.
- */
- selratio = -1;
+ selratio = (min_cnt_d * min_cnt_d + max_cnt_d * max_cnt_d + null_cnt_d * null_cnt_d) / (total * total);
}
else
{
- if (VacAttrStatsLtGtValid(stats) &&
- stats->min_cnt + stats->max_cnt == stats->nonnull_cnt)
- {
-
- /*
- * exact result when there are just 1 or 2
- * values...
- */
- double min_cnt_d = stats->min_cnt,
- max_cnt_d = stats->max_cnt,
- null_cnt_d = stats->null_cnt;
- double total = ((double) stats->nonnull_cnt) + null_cnt_d;
-
- selratio = (min_cnt_d * min_cnt_d + max_cnt_d * max_cnt_d + null_cnt_d * null_cnt_d) / (total * total);
- }
- else
- {
- double most = (double) (stats->best_cnt > stats->null_cnt ? stats->best_cnt : stats->null_cnt);
- double total = ((double) stats->nonnull_cnt) + ((double) stats->null_cnt);
+ double most = (double) (stats->best_cnt > stats->null_cnt ? stats->best_cnt : stats->null_cnt);
+ double total = ((double) stats->nonnull_cnt) + ((double) stats->null_cnt);
- /*
- * we assume count of other values are 20% of best
- * count in table
- */
- selratio = (most * most + 0.20 * most * (total - most)) / (total * total);
- }
- /* Make sure calculated values are in-range */
- if (selratio < 0.0)
- selratio = 0.0;
- else if (selratio > 1.0)
- selratio = 1.0;
+ /*
+ * we assume count of other values are 20% of best
+ * count in table
+ */
+ selratio = (most * most + 0.20 * most * (total - most)) / (total * total);
}
+ /* Make sure calculated values are in-range */
+ if (selratio < 0.0)
+ selratio = 0.0;
+ else if (selratio > 1.0)
+ selratio = 1.0;
+ }
- /* overwrite the existing statistics in the tuple */
- attp->attdisbursion = selratio;
+ /* overwrite the existing statistics in the tuple */
+ attp->attdisbursion = selratio;
- /* invalidate the tuple in the cache and write the buffer */
- RelationInvalidateHeapTuple(ad, atup);
- WriteNoReleaseBuffer(scan->rs_cbuf);
+ /* invalidate the tuple in the cache and write the buffer */
+ RelationInvalidateHeapTuple(ad, atup);
+ WriteNoReleaseBuffer(scan->rs_cbuf);
- /*
- * Create pg_statistic tuples for the relation, if we have
- * gathered the right data. del_stats() previously
- * deleted all the pg_statistic tuples for the rel, so we
- * just have to insert new ones here.
+ /*
+ * Create pg_statistic tuples for the relation, if we have
+ * gathered the right data. del_stats() previously
+ * deleted all the pg_statistic tuples for the rel, so we
+ * just have to insert new ones here.
+ *
+ * Note vacuum_rel() has seen to it that we won't come here
+ * when vacuuming pg_statistic itself.
+ */
+ if (VacAttrStatsLtGtValid(stats) && stats->initialized)
+ {
+ float32data nullratio;
+ float32data bestratio;
+ FmgrInfo out_function;
+ char *out_string;
+ double best_cnt_d = stats->best_cnt,
+ null_cnt_d = stats->null_cnt,
+ nonnull_cnt_d = stats->nonnull_cnt; /* prevent overflow */
+ Datum values[Natts_pg_statistic];
+ char nulls[Natts_pg_statistic];
+
+ nullratio = null_cnt_d / (nonnull_cnt_d + null_cnt_d);
+ bestratio = best_cnt_d / (nonnull_cnt_d + null_cnt_d);
+
+ fmgr_info(stats->outfunc, &out_function);
+
+ for (i = 0; i < Natts_pg_statistic; ++i)
+ nulls[i] = ' ';
+
+ /* ----------------
+ * initialize values[]
+ * ----------------
+ */
+ i = 0;
+ values[i++] = (Datum) relid; /* starelid */
+ values[i++] = (Datum) attp->attnum; /* staattnum */
+ values[i++] = (Datum) stats->op_cmplt; /* staop */
+ /* hack: this code knows float4 is pass-by-ref */
+ values[i++] = PointerGetDatum(&nullratio); /* stanullfrac */
+ values[i++] = PointerGetDatum(&bestratio); /* stacommonfrac */
+ out_string = (*fmgr_faddr(&out_function)) (stats->best, stats->typelem, stats->attr->atttypmod);
+ values[i++] = PointerGetDatum(textin(out_string)); /* stacommonval */
+ pfree(out_string);
+ out_string = (*fmgr_faddr(&out_function)) (stats->min, stats->typelem, stats->attr->atttypmod);
+ values[i++] = PointerGetDatum(textin(out_string)); /* staloval */
+ pfree(out_string);
+ out_string = (char *) (*fmgr_faddr(&out_function)) (stats->max, stats->typelem, stats->attr->atttypmod);
+ values[i++] = PointerGetDatum(textin(out_string)); /* stahival */
+ pfree(out_string);
+
+ stup = heap_formtuple(sd->rd_att, values, nulls);
+
+ /* ----------------
+ * Watch out for oversize tuple, which can happen if
+ * all three of the saved data values are long.
+ * Our fallback strategy is just to not store the
+ * pg_statistic tuple at all in that case. (We could
+ * replace the values by NULLs and still store the
+ * numeric stats, but presently selfuncs.c couldn't
+ * do anything useful with that case anyway.)
*
- * Note vacuum_rel() has seen to it that we won't come here
- * when vacuuming pg_statistic itself.
+ * We could reduce the probability of overflow, but not
+ * prevent it, by storing the data values as compressed
+ * text; is that worth doing? The problem should go
+ * away whenever long tuples get implemented...
+ * ----------------
*/
- if (VacAttrStatsLtGtValid(stats) && stats->initialized)
+ if (MAXALIGN(stup->t_len) <= MaxTupleSize)
{
- float32data nullratio;
- float32data bestratio;
- FmgrInfo out_function;
- char *out_string;
- double best_cnt_d = stats->best_cnt,
- null_cnt_d = stats->null_cnt,
- nonnull_cnt_d = stats->nonnull_cnt; /* prevent overflow */
- Datum values[Natts_pg_statistic];
- char nulls[Natts_pg_statistic];
-
- nullratio = null_cnt_d / (nonnull_cnt_d + null_cnt_d);
- bestratio = best_cnt_d / (nonnull_cnt_d + null_cnt_d);
-
- fmgr_info(stats->outfunc, &out_function);
-
- for (i = 0; i < Natts_pg_statistic; ++i)
- nulls[i] = ' ';
-
- /* ----------------
- * initialize values[]
- * ----------------
- */
- i = 0;
- values[i++] = (Datum) relid; /* starelid */
- values[i++] = (Datum) attp->attnum; /* staattnum */
- values[i++] = (Datum) stats->op_cmplt; /* staop */
- /* hack: this code knows float4 is pass-by-ref */
- values[i++] = PointerGetDatum(&nullratio); /* stanullfrac */
- values[i++] = PointerGetDatum(&bestratio); /* stacommonfrac */
- out_string = (*fmgr_faddr(&out_function)) (stats->best, stats->typelem, stats->attr->atttypmod);
- values[i++] = PointerGetDatum(textin(out_string)); /* stacommonval */
- pfree(out_string);
- out_string = (*fmgr_faddr(&out_function)) (stats->min, stats->typelem, stats->attr->atttypmod);
- values[i++] = PointerGetDatum(textin(out_string)); /* staloval */
- pfree(out_string);
- out_string = (char *) (*fmgr_faddr(&out_function)) (stats->max, stats->typelem, stats->attr->atttypmod);
- values[i++] = PointerGetDatum(textin(out_string)); /* stahival */
- pfree(out_string);
-
- stup = heap_formtuple(sd->rd_att, values, nulls);
-
- /* ----------------
- * Watch out for oversize tuple, which can happen if
- * all three of the saved data values are long.
- * Our fallback strategy is just to not store the
- * pg_statistic tuple at all in that case. (We could
- * replace the values by NULLs and still store the
- * numeric stats, but presently selfuncs.c couldn't
- * do anything useful with that case anyway.)
- *
- * We could reduce the probability of overflow, but not
- * prevent it, by storing the data values as compressed
- * text; is that worth doing? The problem should go
- * away whenever long tuples get implemented...
- * ----------------
- */
- if (MAXALIGN(stup->t_len) <= MaxTupleSize)
- {
- /* OK, store tuple and update indexes too */
- Relation irelations[Num_pg_statistic_indices];
+ /* OK, store tuple and update indexes too */
+ Relation irelations[Num_pg_statistic_indices];
- heap_insert(sd, stup);
- CatalogOpenIndices(Num_pg_statistic_indices, Name_pg_statistic_indices, irelations);
- CatalogIndexInsert(irelations, Num_pg_statistic_indices, sd, stup);
- CatalogCloseIndices(Num_pg_statistic_indices, irelations);
- }
-
- /* release allocated space */
- pfree(DatumGetPointer(values[Anum_pg_statistic_stacommonval - 1]));
- pfree(DatumGetPointer(values[Anum_pg_statistic_staloval - 1]));
- pfree(DatumGetPointer(values[Anum_pg_statistic_stahival - 1]));
- heap_freetuple(stup);
+ heap_insert(sd, stup);
+ CatalogOpenIndices(Num_pg_statistic_indices, Name_pg_statistic_indices, irelations);
+ CatalogIndexInsert(irelations, Num_pg_statistic_indices, sd, stup);
+ CatalogCloseIndices(Num_pg_statistic_indices, irelations);
}
+
+ /* release allocated space */
+ pfree(DatumGetPointer(values[Anum_pg_statistic_stacommonval - 1]));
+ pfree(DatumGetPointer(values[Anum_pg_statistic_staloval - 1]));
+ pfree(DatumGetPointer(values[Anum_pg_statistic_stahival - 1]));
+ heap_freetuple(stup);
}
}
- heap_endscan(scan);
- /* close rels, but hold locks till upcoming commit */
- heap_close(ad, NoLock);
- heap_close(sd, NoLock);
}
+ heap_endscan(scan);
+ /* close rels, but hold locks till upcoming commit */
+ heap_close(ad, NoLock);
+ heap_close(sd, NoLock);
}
/*
}
+/*
+ * This routines handle a special cross-transaction portal.
+ * However it is automatically closed in case of abort.
+ */
+void
+CommonSpecialPortalOpen(void)
+{
+ char *pname;
+
+
+ if (CommonSpecialPortalInUse)
+ elog(ERROR, "CommonSpecialPortal is in use");
+
+ /*
+ * Create a portal for safe memory across transactions. We need to
+ * palloc the name space for it because our hash function expects the
+ * name to be on a longword boundary. CreatePortal copies the name to
+ * safe storage for us.
+ */
+ pname = pstrdup(VACPNAME);
+ vac_portal = CreatePortal(pname);
+ pfree(pname);
+
+ /*
+ * Set flag to indicate that vac_portal must be removed after an error.
+ * This global variable is checked in the transaction manager on xact
+ * abort, and the routine CommonSpecialPortalClose() is called if
+ * necessary.
+ */
+ CommonSpecialPortalInUse = true;
+}
+
+void
+CommonSpecialPortalClose(void)
+{
+ /* Clear flag first, to avoid recursion if PortalDrop elog's */
+ CommonSpecialPortalInUse = false;
+
+ /*
+ * Release our portal for cross-transaction memory.
+ */
+ PortalDrop(&vac_portal);
+}
+
+PortalVariableMemory
+CommonSpecialPortalGetMemory(void)
+{
+ return PortalGetVariableMemory(vac_portal);
+}
+
+bool
+CommonSpecialPortalIsOpen(void)
+{
+ return CommonSpecialPortalInUse;
+}
+
static void
get_indices(Oid relid, int *nindices, Relation **Irel)
{
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