From 5dfd564b1001f20c9def6ae938a92f39ddbd9984 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Thu, 22 Jun 2017 13:17:08 -0400
Subject: [PATCH] Fix IF NOT EXISTS in CREATE STATISTICS
I misplaced the IF NOT EXISTS clause in commit 7b504eb282, before the
word STATISTICS. Put it where it belongs.
Patch written independently by Amit Langote and myself. I adopted his
submitted test case with a slight edit also.
Reported-by: Bruno Wolff III
Discussion: https://postgr.es/m/20170621004237.GB8337@wolff.to
---
src/backend/parser/gram.y | 25 ++++++++++++++++++-------
src/test/regress/expected/stats_ext.out | 6 ++++--
src/test/regress/sql/stats_ext.sql | 5 +++--
3 files changed, 25 insertions(+), 11 deletions(-)
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index ada95e5bc37..0f3998ff893 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -3834,7 +3834,7 @@ ExistingIndex: USING INDEX index_name { $$ = $3; }
/*****************************************************************************
*
* QUERY :
- * CREATE STATISTICS stats_name [(stat types)]
+ * CREATE STATISTICS [IF NOT EXISTS] stats_name [(stat types)]
* ON expression-list FROM from_list
*
* Note: the expectation here is that the clauses after ON are a subset of
@@ -3846,15 +3846,26 @@ ExistingIndex: USING INDEX index_name { $$ = $3; }
*****************************************************************************/
CreateStatsStmt:
- CREATE opt_if_not_exists STATISTICS any_name
+ CREATE STATISTICS any_name
opt_name_list ON expr_list FROM from_list
{
CreateStatsStmt *n = makeNode(CreateStatsStmt);
- n->defnames = $4;
- n->stat_types = $5;
- n->exprs = $7;
- n->relations = $9;
- n->if_not_exists = $2;
+ n->defnames = $3;
+ n->stat_types = $4;
+ n->exprs = $6;
+ n->relations = $8;
+ n->if_not_exists = false;
+ $$ = (Node *)n;
+ }
+ | CREATE STATISTICS IF_P NOT EXISTS any_name
+ opt_name_list ON expr_list FROM from_list
+ {
+ CreateStatsStmt *n = makeNode(CreateStatsStmt);
+ n->defnames = $6;
+ n->stat_types = $7;
+ n->exprs = $9;
+ n->relations = $11;
+ n->if_not_exists = true;
$$ = (Node *)n;
}
;
diff --git a/src/test/regress/expected/stats_ext.out b/src/test/regress/expected/stats_ext.out
index 5fd1244bcb6..085dce7fd78 100644
--- a/src/test/regress/expected/stats_ext.out
+++ b/src/test/regress/expected/stats_ext.out
@@ -30,9 +30,11 @@ CREATE STATISTICS tst ON (relpages, reltuples) FROM pg_class;
ERROR: only simple column references are allowed in CREATE STATISTICS
CREATE STATISTICS tst (unrecognized) ON relname, relnatts FROM pg_class;
ERROR: unrecognized statistic type "unrecognized"
--- Ensure stats are dropped sanely
+-- Ensure stats are dropped sanely, and test IF NOT EXISTS while at it
CREATE TABLE ab1 (a INTEGER, b INTEGER, c INTEGER);
-CREATE STATISTICS ab1_a_b_stats ON a, b FROM ab1;
+CREATE STATISTICS IF NOT EXISTS ab1_a_b_stats ON a, b FROM ab1;
+CREATE STATISTICS IF NOT EXISTS ab1_a_b_stats ON a, b FROM ab1;
+NOTICE: statistics object "ab1_a_b_stats" already exists, skipping
DROP STATISTICS ab1_a_b_stats;
CREATE SCHEMA regress_schema_2;
CREATE STATISTICS regress_schema_2.ab1_a_b_stats ON a, b FROM ab1;
diff --git a/src/test/regress/sql/stats_ext.sql b/src/test/regress/sql/stats_ext.sql
index 4c2f514b933..d1ff3a8583e 100644
--- a/src/test/regress/sql/stats_ext.sql
+++ b/src/test/regress/sql/stats_ext.sql
@@ -18,9 +18,10 @@ CREATE STATISTICS tst ON relnatts + relpages FROM pg_class;
CREATE STATISTICS tst ON (relpages, reltuples) FROM pg_class;
CREATE STATISTICS tst (unrecognized) ON relname, relnatts FROM pg_class;
--- Ensure stats are dropped sanely
+-- Ensure stats are dropped sanely, and test IF NOT EXISTS while at it
CREATE TABLE ab1 (a INTEGER, b INTEGER, c INTEGER);
-CREATE STATISTICS ab1_a_b_stats ON a, b FROM ab1;
+CREATE STATISTICS IF NOT EXISTS ab1_a_b_stats ON a, b FROM ab1;
+CREATE STATISTICS IF NOT EXISTS ab1_a_b_stats ON a, b FROM ab1;
DROP STATISTICS ab1_a_b_stats;
CREATE SCHEMA regress_schema_2;