Hi,
The above query is so simple so that we would better to use the following query:
# This query works on PG10 or later
SELECT
es.stxnamespace::pg_catalog.regnamespace::text AS "Schema",
es.stxname AS "Name",
pg_catalog.format('%s FROM %s',
(SELECT pg_catalog.string_agg(pg_catalog.quote_ident(a.attname),', ')
FROM pg_catalog.unnest(es.stxkeys) s(attnum)
JOIN pg_catalog.pg_attribute a
ON (es.stxrelid = a.attrelid
AND a.attnum = s.attnum
AND NOT a.attisdropped)),
es.stxrelid::regclass) AS "Definition",
CASE WHEN 'd' = any(es.stxkind) THEN 'defined'
END AS "Ndistinct",
CASE WHEN 'f' = any(es.stxkind) THEN 'defined'
END AS "Dependencies",
CASE WHEN 'm' = any(es.stxkind) THEN 'defined'
END AS "MCV"
FROM pg_catalog.pg_statistic_ext es
ORDER BY 1, 2;
Schema | Name | Definition | Ndistinct | Dependencies |
Dependencies
--------+------------+------------------+-----------+--------------+--------------
public | hoge1_ext | a, b FROM hoge1 | defined | defined | defined
public | hoge_t_ext | a, b FROM hoge_t | defined | defined | defined
(2 rows)
I'm going to create the WIP patch to use the above query.
Any comments welcome. :-D
Attached patch is WIP patch.
The changes are:
- Use pg_statistic_ext only
- Remove these statuses: "required" and "built"
- Add new status: "defined"
- Remove the size columns
- Fix document
I'll create and send the regression test on the next patch if there is
no objection. Is it Okay?
Regards,
Tatsuro Yamada
diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index 221a967bfe..36a79d9e3f 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -1918,6 +1918,26 @@ testdb=>
</para>
</listitem>
</varlistentry>
+
+ <varlistentry>
+ <term><literal>\dX [ <link linkend="app-psql-patterns"><replaceable
class="parameter">pattern</replaceable></link> ]</literal></term>
+ <listitem>
+ <para>
+ Lists extended statistics.
+ If <replaceable class="parameter">pattern</replaceable>
+ is specified, only those extended statistics whose names match the
+ pattern are listed.
+ </para>
+
+ <para>
+ The column of the kind of extended stats (e.g. Ndistinct) shows its
status.
+ NULL means that it doesn't exists. "defined" means that it is declared.
+ You can use pg_stats_ext if you'd like to know whether <link
linkend="sql-analyze">
+ <command>ANALYZE</command></link> was run and statistics are available
to the
+ planner.
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term><literal>\dy[+] [ <link linkend="app-psql-patterns"><replaceable
class="parameter">pattern</replaceable></link> ]</literal></term>
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 303e7c3ad8..c98e3d31d0 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -928,6 +928,9 @@ exec_command_d(PsqlScanState scan_state, bool
active_branch, const char *cmd)
else
success = listExtensions(pattern);
break;
+ case 'X': /* Extended Statistics
*/
+ success = listExtendedStats(pattern);
+ break;
case 'y': /* Event Triggers */
success = listEventTriggers(pattern,
show_verbose);
break;
diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index caf97563f4..899fe5d85c 100644
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -4392,6 +4392,89 @@ listEventTriggers(const char *pattern, bool verbose)
return true;
}
+/*
+ * \dX
+ *
+ * Describes extended statistics.
+ */
+bool
+listExtendedStats(const char *pattern)
+{
+ PQExpBufferData buf;
+ PGresult *res;
+ printQueryOpt myopt = pset.popt;
+
+ if (pset.sversion < 100000)
+ {
+ char sverbuf[32];
+
+ pg_log_error("The server (version %s) does not support extended
statistics.",
+ formatPGVersionNumber(pset.sversion,
false,
+
sverbuf, sizeof(sverbuf)));
+ return true;
+ }
+
+ initPQExpBuffer(&buf);
+ printfPQExpBuffer(&buf,
+ "SELECT \n"
+
"es.stxnamespace::pg_catalog.regnamespace::text AS \"%s\", \n"
+ "es.stxname AS \"%s\", \n"
+ "pg_catalog.format('%%s FROM %%s', \n"
+ " (SELECT
pg_catalog.string_agg(pg_catalog.quote_ident(a.attname),', ') \n"
+ " FROM
pg_catalog.unnest(es.stxkeys) s(attnum) \n"
+ " JOIN pg_catalog.pg_attribute a \n"
+ " ON (es.stxrelid = a.attrelid \n"
+ " AND a.attnum = s.attnum \n"
+ " AND NOT a.attisdropped)), \n"
+ "es.stxrelid::regclass) AS \"%s\"",
+ gettext_noop("Schema"),
+ gettext_noop("Name"),
+ gettext_noop("Definition"));
+
+ appendPQExpBuffer(&buf,
+ ",\nCASE WHEN 'd' = any(es.stxkind)
THEN 'defined' \n"
+ "END AS \"%s\", \n"
+ "CASE WHEN 'f' = any(es.stxkind) THEN
'defined' \n"
+ "END AS \"%s\"",
+ gettext_noop("Ndistinct"),
+ gettext_noop("Dependencies"));
+
+ /*
+ * Add the MCV statistics kind.
+ */
+ if (pset.sversion >= 120000)
+ {
+ appendPQExpBuffer(&buf,
+ ",\nCASE WHEN 'm' =
any(es.stxkind) THEN 'defined' \n"
+ "END AS \"%s\" ",
+ gettext_noop("MCV"));
+ }
+
+ appendPQExpBufferStr(&buf,
+ " \nFROM
pg_catalog.pg_statistic_ext es \n");
+
+ processSQLNamePattern(pset.db, &buf, pattern, false,
+ false, NULL,
+ "es.stxname", NULL,
+ NULL);
+
+ appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
+
+ res = PSQLexec(buf.data);
+ termPQExpBuffer(&buf);
+ if (!res)
+ return false;
+
+ myopt.nullPrint = NULL;
+ myopt.title = _("List of extended statistics");
+ myopt.translate_header = true;
+
+ printQuery(res, &myopt, pset.queryFout, false, pset.logfile);
+
+ PQclear(res);
+ return true;
+}
+
/*
* \dC
*
diff --git a/src/bin/psql/describe.h b/src/bin/psql/describe.h
index 6044e3a082..39856a0c7e 100644
--- a/src/bin/psql/describe.h
+++ b/src/bin/psql/describe.h
@@ -102,6 +102,9 @@ extern bool listExtensions(const char *pattern);
/* \dx+ */
extern bool listExtensionContents(const char *pattern);
+/* \dX */
+extern bool listExtendedStats(const char *pattern);
+
/* \dy */
extern bool listEventTriggers(const char *pattern, bool verbose);
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 9ec1c4e810..4883ebd2ed 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -267,6 +267,7 @@ slashUsage(unsigned short int pager)
fprintf(output, _(" \\du[S+] [PATTERN] list roles\n"));
fprintf(output, _(" \\dv[S+] [PATTERN] list views\n"));
fprintf(output, _(" \\dx[+] [PATTERN] list extensions\n"));
+ fprintf(output, _(" \\dX [PATTERN] list extended
statistics\n"));
fprintf(output, _(" \\dy [PATTERN] list event triggers\n"));
fprintf(output, _(" \\l[+] [PATTERN] list databases\n"));
fprintf(output, _(" \\sf[+] FUNCNAME show a function's
definition\n"));
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 6abcbea963..17f7265038 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -1505,7 +1505,7 @@ psql_completion(const char *text, int start, int end)
"\\dF", "\\dFd", "\\dFp", "\\dFt", "\\dg", "\\di", "\\dl",
"\\dL",
"\\dm", "\\dn", "\\do", "\\dO", "\\dp", "\\dP", "\\dPi",
"\\dPt",
"\\drds", "\\dRs", "\\dRp", "\\ds", "\\dS",
- "\\dt", "\\dT", "\\dv", "\\du", "\\dx", "\\dy",
+ "\\dt", "\\dT", "\\dv", "\\du", "\\dx", "\\dX", "\\dy",
"\\e", "\\echo", "\\ef", "\\elif", "\\else", "\\encoding",
"\\endif", "\\errverbose", "\\ev",
"\\f",
@@ -3974,6 +3974,8 @@ psql_completion(const char *text, int start, int end)
COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_views, NULL);
else if (TailMatchesCS("\\dx*"))
COMPLETE_WITH_QUERY(Query_for_list_of_extensions);
+ else if (TailMatchesCS("\\dX*"))
+ COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_statistics, NULL);
else if (TailMatchesCS("\\dm*"))
COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_matviews, NULL);
else if (TailMatchesCS("\\dE*"))
