On Sun, Jul 07, 2019 at 12:02:38AM +0200, Tomas Vondra wrote:
Hi,
apparently v1 of the ALTER STATISTICS patch was a bit confused about
length of the VacAttrStats array passed to statext_compute_stattarget,
causing segfaults. Attached v2 patch fixes that, and it also makes sure
we print warnings about ignored statistics only once.
v3 of the patch, adding pg_dump support - it works just like when you
tweak statistics target for a column, for example. When the value stored
in the catalog is not -1, pg_dump emits a separate ALTER STATISTICS
command setting it (for the already created statistics object).
I've considered making it part of CREATE STATISTICS itself, but it seems
a bit cumbersome and we don't do it for columns either. I'm not against
adding it in the future, but at this point I don't see a need.
At this point I'm not aware of any missing or broken pieces, so I'd
welcome feedback.
regards
--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
diff --git a/doc/src/sgml/ref/alter_statistics.sgml
b/doc/src/sgml/ref/alter_statistics.sgml
index 58c7ed020d..987f9dbc6f 100644
--- a/doc/src/sgml/ref/alter_statistics.sgml
+++ b/doc/src/sgml/ref/alter_statistics.sgml
@@ -26,6 +26,7 @@ PostgreSQL documentation
ALTER STATISTICS <replaceable class="parameter">name</replaceable> OWNER TO {
<replaceable class="parameter">new_owner</replaceable> | CURRENT_USER |
SESSION_USER }
ALTER STATISTICS <replaceable class="parameter">name</replaceable> RENAME TO
<replaceable class="parameter">new_name</replaceable>
ALTER STATISTICS <replaceable class="parameter">name</replaceable> SET SCHEMA
<replaceable class="parameter">new_schema</replaceable>
+ALTER STATISTICS <replaceable class="parameter">name</replaceable> SET
STATISTICS <replaceable class="parameter">new_target</replaceable>
</synopsis>
</refsynopsisdiv>
@@ -93,6 +94,22 @@ ALTER STATISTICS <replaceable
class="parameter">name</replaceable> SET SCHEMA <r
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><replaceable class="parameter">new_target</replaceable></term>
+ <listitem>
+ <para>
+ The statistic-gathering target for this statistic object for subsequent
+ <xref linkend="sql-analyze"/> operations.
+ The target can be set in the range 0 to 10000; alternatively, set it
+ to -1 to revert to using the system default statistics
+ target (<xref linkend="guc-default-statistics-target"/>).
+ For more information on the use of statistics by the
+ <productname>PostgreSQL</productname> query planner, refer to
+ <xref linkend="planner-stats"/>.
+ </para>
+ </listitem>
+ </varlistentry>
+
</variablelist>
</para>
</refsect1>
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index d7004e5313..caa4fca99d 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -490,6 +490,19 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
}
}
+ /*
+ * Look at extended statistic objects too, because those may define
their
+ * own statistic target. So we need to sample enough rows and then build
+ * the statistics with enough detail.
+ */
+ {
+ int nrows = ComputeExtStatisticsTarget(onerel,
+
attr_cnt, vacattrstats);
+
+ if (targrows < nrows)
+ targrows = nrows;
+ }
+
/*
* Acquire the sample rows
*/
diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index cf406f6f96..356b6096ac 100644
--- a/src/backend/commands/statscmds.c
+++ b/src/backend/commands/statscmds.c
@@ -14,6 +14,7 @@
*/
#include "postgres.h"
+#include "access/heapam.h"
#include "access/relation.h"
#include "access/relscan.h"
#include "access/table.h"
@@ -21,6 +22,7 @@
#include "catalog/dependency.h"
#include "catalog/indexing.h"
#include "catalog/namespace.h"
+#include "catalog/objectaccess.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_statistic_ext.h"
#include "catalog/pg_statistic_ext_data.h"
@@ -29,6 +31,7 @@
#include "miscadmin.h"
#include "statistics/statistics.h"
#include "utils/builtins.h"
+#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/memutils.h"
#include "utils/rel.h"
@@ -336,6 +339,7 @@ CreateStatistics(CreateStatsStmt *stmt)
values[Anum_pg_statistic_ext_stxrelid - 1] = ObjectIdGetDatum(relid);
values[Anum_pg_statistic_ext_stxname - 1] = NameGetDatum(&stxname);
values[Anum_pg_statistic_ext_stxnamespace - 1] =
ObjectIdGetDatum(namespaceId);
+ values[Anum_pg_statistic_ext_stxstattarget - 1] = Int32GetDatum(-1);
values[Anum_pg_statistic_ext_stxowner - 1] = ObjectIdGetDatum(stxowner);
values[Anum_pg_statistic_ext_stxkeys - 1] = PointerGetDatum(stxkeys);
values[Anum_pg_statistic_ext_stxkind - 1] = PointerGetDatum(stxkind);
@@ -414,6 +418,85 @@ CreateStatistics(CreateStatsStmt *stmt)
return myself;
}
+
+/*
+ * ALTER STATISTICS
+ */
+ObjectAddress
+AlterStatistics(AlterStatsStmt *stmt)
+{
+ Relation rel;
+ Oid stxoid;
+ HeapTuple oldtup;
+ HeapTuple newtup;
+ Datum repl_val[Natts_pg_statistic_ext];
+ bool repl_null[Natts_pg_statistic_ext];
+ bool repl_repl[Natts_pg_statistic_ext];
+ ObjectAddress address;
+ int newtarget = stmt->stxstattarget;
+
+ /* Limit target to a sane range */
+ if (newtarget < -1)
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("statistics target %d is too low",
+ newtarget)));
+ }
+ else if (newtarget > 10000)
+ {
+ newtarget = 10000;
+ ereport(WARNING,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("lowering statistics target to %d",
+ newtarget)));
+ }
+
+ /* lookup OID of the statistic object */
+ stxoid = get_statistics_object_oid(stmt->defnames, false);
+
+ /* Search pg_statistic_ext */
+ rel = table_open(StatisticExtRelationId, RowExclusiveLock);
+
+ oldtup = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(stxoid));
+
+ /* Must be owner of the existing statistic object */
+ if (!pg_statistics_object_ownercheck(stxoid, GetUserId()))
+ aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_STATISTIC_EXT,
+ NameListToString(stmt->defnames));
+
+ /* Build new tuple. */
+ memset(repl_val, 0, sizeof(repl_val));
+ memset(repl_null, false, sizeof(repl_null));
+ memset(repl_repl, false, sizeof(repl_repl));
+
+ /* replace the stxstattarget column */
+ repl_repl[Anum_pg_statistic_ext_stxstattarget - 1] = true;
+ repl_val[Anum_pg_statistic_ext_stxstattarget - 1] =
Int32GetDatum(newtarget);
+
+ newtup = heap_modify_tuple(oldtup, RelationGetDescr(rel),
+ repl_val, repl_null,
repl_repl);
+
+ /* Update system catalog. */
+ CatalogTupleUpdate(rel, &newtup->t_self, newtup);
+
+ InvokeObjectPostAlterHook(StatisticExtRelationId, stxoid, 0);
+
+ ObjectAddressSet(address, StatisticExtRelationId, stxoid);
+
+ /*
+ * NOTE: because we only support altering the statistic target, not the
+ * other fields, there is no need to update dependencies.
+ */
+
+ heap_freetuple(newtup);
+ ReleaseSysCache(oldtup);
+
+ table_close(rel, RowExclusiveLock);
+
+ return address;
+}
+
/*
* Guts of statistics object deletion.
*/
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 78deade89b..048239fe34 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -3493,6 +3493,18 @@ _copyCreateStatsStmt(const CreateStatsStmt *from)
return newnode;
}
+static AlterStatsStmt *
+_copyAlterStatsStmt(const AlterStatsStmt *from)
+{
+ AlterStatsStmt *newnode = makeNode(AlterStatsStmt);
+
+ COPY_NODE_FIELD(defnames);
+ COPY_SCALAR_FIELD(stxstattarget);
+ COPY_SCALAR_FIELD(if_not_exists);
+
+ return newnode;
+}
+
static CreateFunctionStmt *
_copyCreateFunctionStmt(const CreateFunctionStmt *from)
{
@@ -5249,6 +5261,9 @@ copyObjectImpl(const void *from)
case T_CreateStatsStmt:
retval = _copyCreateStatsStmt(from);
break;
+ case T_AlterStatsStmt:
+ retval = _copyAlterStatsStmt(from);
+ break;
case T_CreateFunctionStmt:
retval = _copyCreateFunctionStmt(from);
break;
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index 4f2ebe5118..4c35cdf41e 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -1365,6 +1365,16 @@ _equalCreateStatsStmt(const CreateStatsStmt *a, const
CreateStatsStmt *b)
return true;
}
+static bool
+_equalAlterStatsStmt(const AlterStatsStmt *a, const AlterStatsStmt *b)
+{
+ COMPARE_NODE_FIELD(defnames);
+ COMPARE_SCALAR_FIELD(stxstattarget);
+ COMPARE_SCALAR_FIELD(if_not_exists);
+
+ return true;
+}
+
static bool
_equalCreateFunctionStmt(const CreateFunctionStmt *a, const CreateFunctionStmt
*b)
{
@@ -3309,6 +3319,9 @@ equal(const void *a, const void *b)
case T_CreateStatsStmt:
retval = _equalCreateStatsStmt(a, b);
break;
+ case T_AlterStatsStmt:
+ retval = _equalAlterStatsStmt(a, b);
+ break;
case T_CreateFunctionStmt:
retval = _equalCreateFunctionStmt(a, b);
break;
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 8400dd319e..4551d7a023 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -2662,6 +2662,16 @@ _outCreateStatsStmt(StringInfo str, const
CreateStatsStmt *node)
WRITE_BOOL_FIELD(if_not_exists);
}
+static void
+_outAlterStatsStmt(StringInfo str, const AlterStatsStmt *node)
+{
+ WRITE_NODE_TYPE("ALTERSTATSSTMT");
+
+ WRITE_NODE_FIELD(defnames);
+ WRITE_INT_FIELD(stxstattarget);
+ WRITE_BOOL_FIELD(if_not_exists);
+}
+
static void
_outNotifyStmt(StringInfo str, const NotifyStmt *node)
{
@@ -4124,6 +4134,9 @@ outNode(StringInfo str, const void *obj)
case T_CreateStatsStmt:
_outCreateStatsStmt(str, obj);
break;
+ case T_AlterStatsStmt:
+ _outAlterStatsStmt(str, obj);
+ break;
case T_NotifyStmt:
_outNotifyStmt(str, obj);
break;
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 208b4a1f28..29e24fdfea 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -252,7 +252,7 @@ static Node *makeRecursiveViewSelect(char *relname, List
*aliases, Node *query);
AlterOperatorStmt AlterSeqStmt AlterSystemStmt AlterTableStmt
AlterTblSpcStmt AlterExtensionStmt AlterExtensionContentsStmt
AlterForeignTableStmt
AlterCompositeTypeStmt AlterUserMappingStmt
- AlterRoleStmt AlterRoleSetStmt AlterPolicyStmt
+ AlterRoleStmt AlterRoleSetStmt AlterPolicyStmt AlterStatsStmt
AlterDefaultPrivilegesStmt DefACLAction
AnalyzeStmt CallStmt ClosePortalStmt ClusterStmt CommentStmt
ConstraintsSetStmt CopyStmt CreateAsStmt CreateCastStmt
@@ -852,6 +852,7 @@ stmt :
| AlterRoleSetStmt
| AlterRoleStmt
| AlterSubscriptionStmt
+ | AlterStatsStmt
| AlterTSConfigurationStmt
| AlterTSDictionaryStmt
| AlterUserMappingStmt
@@ -3984,6 +3985,34 @@ CreateStatsStmt:
}
;
+
+/*****************************************************************************
+ *
+ * QUERY :
+ * ALTER STATISTICS [IF EXISTS] stats_name
+ * SET STATISTICS <SignedIconst>
+ *
+ *****************************************************************************/
+
+AlterStatsStmt:
+ ALTER STATISTICS any_name SET STATISTICS SignedIconst
+ {
+ AlterStatsStmt *n =
makeNode(AlterStatsStmt);
+ n->defnames = $3;
+ n->if_not_exists = false;
+ n->stxstattarget = $6;
+ $$ = (Node *)n;
+ }
+ | ALTER STATISTICS IF_P EXISTS any_name SET STATISTICS
SignedIconst
+ {
+ AlterStatsStmt *n =
makeNode(AlterStatsStmt);
+ n->defnames = $5;
+ n->if_not_exists = true;
+ n->stxstattarget = $8;
+ $$ = (Node *)n;
+ }
+ ;
+
/*****************************************************************************
*
* QUERY :
diff --git a/src/backend/statistics/extended_stats.c
b/src/backend/statistics/extended_stats.c
index c56ed48270..f0d0deabaf 100644
--- a/src/backend/statistics/extended_stats.c
+++ b/src/backend/statistics/extended_stats.c
@@ -61,6 +61,7 @@ typedef struct StatExtEntry
char *name; /* statistics object's name */
Bitmapset *columns; /* attribute numbers covered by the
object */
List *types; /* 'char' list of enabled
statistic kinds */
+ int stattarget; /* statistic target (-1
for default) */
} StatExtEntry;
@@ -70,7 +71,8 @@ static VacAttrStats **lookup_var_attr_stats(Relation rel,
Bitmapset *attrs,
static void statext_store(Oid relid,
MVNDistinct *ndistinct,
MVDependencies *dependencies,
MCVList *mcv, VacAttrStats
**stats);
-
+static int statext_compute_stattarget(int stattarget,
+ int
natts, VacAttrStats **stats);
/*
* Compute requested extended stats, using the rows sampled for the plain
@@ -106,6 +108,7 @@ BuildRelationExtStatistics(Relation onerel, double
totalrows,
MCVList *mcv = NULL;
VacAttrStats **stats;
ListCell *lc2;
+ int stattarget;
/*
* Check if we can build these stats based on the column
analyzed. If
@@ -130,6 +133,13 @@ BuildRelationExtStatistics(Relation onerel, double
totalrows,
Assert(bms_num_members(stat->columns) >= 2 &&
bms_num_members(stat->columns) <=
STATS_MAX_DIMENSIONS);
+ /* compute current statistic target */
+ stattarget = statext_compute_stattarget(stat->stattarget,
+
bms_num_members(stat->columns),
+
stats);
+
+ /* XXX What if the target is set to 0? Reset the statistic? */
+
/* compute statistic of each requested type */
foreach(lc2, stat->types)
{
@@ -143,7 +153,7 @@ BuildRelationExtStatistics(Relation onerel, double
totalrows,
stat->columns, stats);
else if (t == STATS_EXT_MCV)
mcv = statext_mcv_build(numrows, rows,
stat->columns, stats,
-
totalrows);
+
totalrows, stattarget);
}
/* store the statistics in the catalog */
@@ -156,6 +166,108 @@ BuildRelationExtStatistics(Relation onerel, double
totalrows,
MemoryContextDelete(cxt);
}
+/*
+ * ComputeExtStatisticsTarget
+ * Compute the largest statistic target for all extended
statistics.
+ */
+int
+ComputeExtStatisticsTarget(Relation onerel,
+ int natts, VacAttrStats
**vacattrstats)
+{
+ Relation pg_stext;
+ ListCell *lc;
+ List *lstats;
+ MemoryContext cxt;
+ MemoryContext oldcxt;
+ int result = 0;
+
+ cxt = AllocSetContextCreate(CurrentMemoryContext,
+
"ComputeExtStatisticsTarget",
+
ALLOCSET_DEFAULT_SIZES);
+ oldcxt = MemoryContextSwitchTo(cxt);
+
+ pg_stext = table_open(StatisticExtRelationId, RowExclusiveLock);
+ lstats = fetch_statentries_for_relation(pg_stext,
RelationGetRelid(onerel));
+
+ foreach(lc, lstats)
+ {
+ StatExtEntry *stat = (StatExtEntry *) lfirst(lc);
+ int stattarget = stat->stattarget;
+ VacAttrStats **stats;
+ int nattrs =
bms_num_members(stat->columns);
+
+ /*
+ * Check if we can build these stats based on the column
analyzed. If
+ * not, report this fact (except in autovacuum) and move on.
+ */
+ stats = lookup_var_attr_stats(onerel, stat->columns,
+
natts, vacattrstats);
+
+ /* ignore statistics we'll skip later */
+ if (!stats)
+ continue;
+
+ /* compute statistic target, based on the statistic object and
attributes */
+ stattarget = statext_compute_stattarget(stat->stattarget,
nattrs, stats);
+
+ /* Use the largest value for all statistic objects. */
+ if (stattarget > result)
+ result = stattarget;
+ }
+
+ table_close(pg_stext, RowExclusiveLock);
+
+ MemoryContextSwitchTo(oldcxt);
+ MemoryContextDelete(cxt);
+
+ return (300 * result);
+}
+
+/*
+ * statext_compute_stattarget
+ * compute statistic target for an extended statistic
+ *
+ * If the statistic object has custom value (set using ALTER STATISTICS ...
+ * SET STATISTICS), then we simply use that. Otherwise we look at targets
+ * for columns the object is defined on and use the largest value. Finally,
+ * if the target is still (-1), we use the default_statistics_target.
+ */
+static int
+statext_compute_stattarget(int stattarget, int nattrs, VacAttrStats **stats)
+{
+ int i;
+
+ /* if there's statistic target set for the statistic object, use it */
+ if (stattarget >= 0)
+ return stattarget;
+
+ /*
+ * The stattarget column is negative, we look at targets for each
+ * column the statistics is based on, and use use the largest value
+ * for any of the columns.
+ */
+ {
+ for (i = 0; i < nattrs; i++)
+ {
+ if (stats[i]->attr->attstattarget > stattarget)
+ stattarget = stats[i]->attr->attstattarget;
+ }
+ }
+
+ /*
+ * If the value is still negative (so neither the extended statistic
+ * object nor any of the columns) have custom statistic target set.
+ * In that case use the default target.
+ */
+ if (stattarget < 0)
+ stattarget = default_statistics_target;
+
+ /* As this point we should have a valid statistic target. */
+ Assert((stattarget >= 0) && (stattarget <= 10000));
+
+ return stattarget;
+}
+
/*
* statext_is_kind_built
* Is this stat kind built in the given pg_statistic_ext_data
tuple?
@@ -224,6 +336,7 @@ fetch_statentries_for_relation(Relation pg_statext, Oid
relid)
entry->statOid = staForm->oid;
entry->schema = get_namespace_name(staForm->stxnamespace);
entry->name = pstrdup(NameStr(staForm->stxname));
+ entry->stattarget = staForm->stxstattarget;
for (i = 0; i < staForm->stxkeys.dim1; i++)
{
entry->columns = bms_add_member(entry->columns,
diff --git a/src/backend/statistics/mcv.c b/src/backend/statistics/mcv.c
index 913a72ff67..8491b20af3 100644
--- a/src/backend/statistics/mcv.c
+++ b/src/backend/statistics/mcv.c
@@ -162,7 +162,8 @@ get_mincount_for_mcv_list(int samplerows, double totalrows)
*/
MCVList *
statext_mcv_build(int numrows, HeapTuple *rows, Bitmapset *attrs,
- VacAttrStats **stats, double totalrows)
+ VacAttrStats **stats, double totalrows,
+ int stattarget)
{
int i,
numattrs,
@@ -194,12 +195,7 @@ statext_mcv_build(int numrows, HeapTuple *rows, Bitmapset
*attrs,
* Maximum number of MCV items to store, based on the attribute with the
* largest stats target (and the number of groups we have available).
*/
- nitems = stats[0]->attr->attstattarget;
- for (i = 1; i < numattrs; i++)
- {
- if (stats[i]->attr->attstattarget > nitems)
- nitems = stats[i]->attr->attstattarget;
- }
+ nitems = stattarget;
if (nitems > ngroups)
nitems = ngroups;
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 05ec7f3ac6..1299066c63 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1688,6 +1688,10 @@ ProcessUtilitySlow(ParseState *pstate,
address = CreateStatistics((CreateStatsStmt *)
parsetree);
break;
+ case T_AlterStatsStmt:
+ address = AlterStatistics((AlterStatsStmt *)
parsetree);
+ break;
+
case T_AlterCollationStmt:
address = AlterCollation((AlterCollationStmt *)
parsetree);
break;
@@ -2805,6 +2809,10 @@ CreateCommandTag(Node *parsetree)
tag = "CREATE STATISTICS";
break;
+ case T_AlterStatsStmt:
+ tag = "ALTER STATISTICS";
+ break;
+
case T_DeallocateStmt:
{
DeallocateStmt *stmt = (DeallocateStmt *)
parsetree;
@@ -3393,6 +3401,10 @@ GetCommandLogLevel(Node *parsetree)
lev = LOGSTMT_DDL;
break;
+ case T_AlterStatsStmt:
+ lev = LOGSTMT_DDL;
+ break;
+
case T_AlterCollationStmt:
lev = LOGSTMT_DDL;
break;
diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 806fc78f04..f40cbaae34 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -7172,6 +7172,7 @@ getExtendedStatistics(Archive *fout)
int i_stxname;
int i_stxnamespace;
int i_rolname;
+ int i_stattarget;
int i;
/* Extended statistics were new in v10 */
@@ -7180,10 +7181,16 @@ getExtendedStatistics(Archive *fout)
query = createPQExpBuffer();
- appendPQExpBuffer(query, "SELECT tableoid, oid, stxname, "
- "stxnamespace, (%s stxowner) AS
rolname "
- "FROM pg_catalog.pg_statistic_ext",
- username_subquery);
+ if (fout->remoteVersion < 130000)
+ appendPQExpBuffer(query, "SELECT tableoid, oid, stxname, "
+ "stxnamespace, (%s stxowner)
AS rolname, (-1) AS stxstattarget "
+ "FROM
pg_catalog.pg_statistic_ext",
+ username_subquery);
+ else
+ appendPQExpBuffer(query, "SELECT tableoid, oid, stxname, "
+ "stxnamespace, (%s stxowner)
AS rolname, stxstattarget "
+ "FROM
pg_catalog.pg_statistic_ext",
+ username_subquery);
res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
@@ -7194,6 +7201,7 @@ getExtendedStatistics(Archive *fout)
i_stxname = PQfnumber(res, "stxname");
i_stxnamespace = PQfnumber(res, "stxnamespace");
i_rolname = PQfnumber(res, "rolname");
+ i_stattarget = PQfnumber(res, "stxstattarget");
statsextinfo = (StatsExtInfo *) pg_malloc(ntups * sizeof(StatsExtInfo));
@@ -7208,7 +7216,8 @@ getExtendedStatistics(Archive *fout)
findNamespace(fout,
atooid(PQgetvalue(res, i,
i_stxnamespace)));
statsextinfo[i].rolname = pg_strdup(PQgetvalue(res, i,
i_rolname));
-
+ statsextinfo[i].stattarget = atoi(PQgetvalue(res, i,
i_stattarget));
+
/* Decide whether we want to dump it */
selectDumpableObject(&(statsextinfo[i].dobj), fout);
@@ -16495,6 +16504,19 @@ dumpStatisticsExt(Archive *fout, StatsExtInfo
*statsextinfo)
/* Result of pg_get_statisticsobjdef is complete except for semicolon */
appendPQExpBuffer(q, "%s;\n", stxdef);
+ /*
+ * We only issue an ALTER STATISTICS statement if the stxstattarget
entry
+ * for this statictics object is non-negative (i.e. it's not the default
+ * value).
+ */
+ if (statsextinfo->stattarget >= 0)
+ {
+ appendPQExpBuffer(q, "ALTER STATISTICS %s ",
+
fmtQualifiedDumpable(statsextinfo));
+ appendPQExpBuffer(q, "SET STATISTICS %d;\n",
+ statsextinfo->stattarget);
+ }
+
appendPQExpBuffer(delq, "DROP STATISTICS %s;\n",
fmtQualifiedDumpable(statsextinfo));
diff --git a/src/bin/pg_dump/pg_dump.h b/src/bin/pg_dump/pg_dump.h
index c3c2ea1473..baaa2a24a0 100644
--- a/src/bin/pg_dump/pg_dump.h
+++ b/src/bin/pg_dump/pg_dump.h
@@ -386,6 +386,7 @@ typedef struct _statsExtInfo
{
DumpableObject dobj;
char *rolname; /* name of owner, or empty string */
+ int stattarget; /* statistic target */
} StatsExtInfo;
typedef struct _ruleInfo
diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl
index c56bf00e4b..7617f35a4f 100644
--- a/src/bin/pg_dump/t/002_pg_dump.pl
+++ b/src/bin/pg_dump/t/002_pg_dump.pl
@@ -2504,6 +2504,17 @@ my %tests = (
unlike => { exclude_dump_test_schema => 1, },
},
+ 'ALTER STATISTICS extended_stats_options' => {
+ create_order => 98,
+ create_sql => 'ALTER STATISTICS dump_test.test_ext_stats_opts
SET STATISTICS 1000',
+ regexp => qr/^
+ \QALTER STATISTICS dump_test.test_ext_stats_opts SET
STATISTICS 1000;\E
+ /xms,
+ like =>
+ { %full_runs, %dump_test_schema_runs, section_post_data => 1,
},
+ unlike => { exclude_dump_test_schema => 1, },
+ },
+
'CREATE SEQUENCE test_table_col1_seq' => {
regexp => qr/^
\QCREATE SEQUENCE dump_test.test_table_col1_seq\E
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 9009b05e12..35a264c29b 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -1840,7 +1840,7 @@ psql_completion(const char *text, int start, int end)
/* ALTER STATISTICS <name> */
else if (Matches("ALTER", "STATISTICS", MatchAny))
- COMPLETE_WITH("OWNER TO", "RENAME TO", "SET SCHEMA");
+ COMPLETE_WITH("OWNER TO", "RENAME TO", "SET SCHEMA", "SET
STATISTICS");
/* ALTER TRIGGER <name>, add ON */
else if (Matches("ALTER", "TRIGGER", MatchAny))
diff --git a/src/include/catalog/pg_statistic_ext.h
b/src/include/catalog/pg_statistic_ext.h
index d8c5e0651e..5f6bfdd56c 100644
--- a/src/include/catalog/pg_statistic_ext.h
+++ b/src/include/catalog/pg_statistic_ext.h
@@ -41,6 +41,7 @@ CATALOG(pg_statistic_ext,3381,StatisticExtRelationId)
Oid stxnamespace; /* OID of statistics object's
namespace */
Oid stxowner; /* statistics object's
owner */
+ int32 stxstattarget BKI_DEFAULT(-1); /* statistic
target */
/*
* variable-length fields start here, but we allow direct access to
diff --git a/src/include/commands/defrem.h b/src/include/commands/defrem.h
index b4e7db67c3..1dc6dc2ca0 100644
--- a/src/include/commands/defrem.h
+++ b/src/include/commands/defrem.h
@@ -87,6 +87,7 @@ extern ObjectAddress AlterOperator(AlterOperatorStmt *stmt);
/* commands/statscmds.c */
extern ObjectAddress CreateStatistics(CreateStatsStmt *stmt);
+extern ObjectAddress AlterStatistics(AlterStatsStmt *stmt);
extern void RemoveStatisticsById(Oid statsOid);
extern void UpdateStatisticsForTypeChange(Oid statsOid,
Oid relationOid, int attnum,
diff --git a/src/include/nodes/nodes.h b/src/include/nodes/nodes.h
index 4e2fb39105..57589d4fac 100644
--- a/src/include/nodes/nodes.h
+++ b/src/include/nodes/nodes.h
@@ -420,6 +420,7 @@ typedef enum NodeTag
T_CreateStatsStmt,
T_AlterCollationStmt,
T_CallStmt,
+ T_AlterStatsStmt,
/*
* TAGS FOR PARSE TREE NODES (parsenodes.h)
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 94ded3c135..a6a3382a46 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2789,6 +2789,18 @@ typedef struct CreateStatsStmt
bool if_not_exists; /* do nothing if stats name already
exists */
} CreateStatsStmt;
+/* ----------------------
+ * Alter Statistics Statement
+ * ----------------------
+ */
+typedef struct AlterStatsStmt
+{
+ NodeTag type;
+ List *defnames; /* qualified name (list of Value
strings) */
+ int stxstattarget; /* statistics target, or NULL */
+ bool if_not_exists; /* do nothing if stats name already
exists */
+} AlterStatsStmt;
+
/* ----------------------
* Create Function Statement
* ----------------------
diff --git a/src/include/statistics/extended_stats_internal.h
b/src/include/statistics/extended_stats_internal.h
index 8fc541993f..71fd509f16 100644
--- a/src/include/statistics/extended_stats_internal.h
+++ b/src/include/statistics/extended_stats_internal.h
@@ -71,7 +71,7 @@ extern MVDependencies *statext_dependencies_deserialize(bytea
*data);
extern MCVList *statext_mcv_build(int numrows, HeapTuple *rows,
Bitmapset
*attrs, VacAttrStats **stats,
- double
totalrows);
+ double
totalrows, int stattarget);
extern bytea *statext_mcv_serialize(MCVList *mcv, VacAttrStats **stats);
extern MCVList *statext_mcv_deserialize(bytea *data);
diff --git a/src/include/statistics/statistics.h
b/src/include/statistics/statistics.h
index cb7bc630e9..53ec906936 100644
--- a/src/include/statistics/statistics.h
+++ b/src/include/statistics/statistics.h
@@ -100,6 +100,8 @@ extern MCVList *statext_mcv_load(Oid mvoid);
extern void BuildRelationExtStatistics(Relation onerel, double totalrows,
int
numrows, HeapTuple *rows,
int
natts, VacAttrStats **vacattrstats);
+extern int ComputeExtStatisticsTarget(Relation onerel,
+ int
natts, VacAttrStats **stats);
extern bool statext_is_kind_built(HeapTuple htup, char kind);
extern Selectivity dependencies_clauselist_selectivity(PlannerInfo *root,
List *clauses,
