20141015_analyze_transactional.patch

From 33dde1068992cc5f0f869efa9bec3e5fa7e912e9 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@otacoo.com>
Date: Wed, 15 Oct 2014 17:09:53 +0900
Subject: [PATCH] Fix non-transactional ANALYZE causing relation
 inconsistencies

When ANALYZE is used within a transaction that changes a given table
schema by some other DDL queries by (manipulating for example indexes,
triggers, etc.), the pg_class entry of this relation was getting updated
in a non-transactional way causing relation definition inconsistencies.
This commit changes ANALYZE to always have it perform transactional updates
of the relation definitions it manipulates in pg_class, to make it
transaction-safe.
---
 src/backend/commands/analyze.c            |  6 ++++--
 src/backend/commands/vacuum.c             | 18 +++++++++++++++---
 src/backend/commands/vacuumlazy.c         |  6 ++++--
 src/include/commands/vacuum.h             |  3 ++-
 src/test/regress/expected/alter_table.out | 20 ++++++++++++++++++++
 src/test/regress/sql/alter_table.sql      | 13 +++++++++++++
 6 files changed, 58 insertions(+), 8 deletions(-)

diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index c09ca7e..f1e447d 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -584,7 +584,8 @@ do_analyze_rel(Relation onerel, VacuumStmt *vacstmt,
 							visibilitymap_count(onerel),
 							hasindex,
 							InvalidTransactionId,
-							InvalidMultiXactId);
+							InvalidMultiXactId,
+							!(vacstmt->options & VACOPT_VACUUM));
 
 	/*
 	 * Same for indexes. Vacuum always scans all indexes, so if we're part of
@@ -605,7 +606,8 @@ do_analyze_rel(Relation onerel, VacuumStmt *vacstmt,
 								0,
 								false,
 								InvalidTransactionId,
-								InvalidMultiXactId);
+								InvalidMultiXactId,
+								!(vacstmt->options & VACOPT_VACUUM));
 		}
 	}
 
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index e5fefa3..6f05a74 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -672,7 +672,7 @@ vac_update_relstats(Relation relation,
 					BlockNumber num_pages, double num_tuples,
 					BlockNumber num_all_visible_pages,
 					bool hasindex, TransactionId frozenxid,
-					MultiXactId minmulti)
+					MultiXactId minmulti, bool is_vacuum)
 {
 	Oid			relid = RelationGetRelid(relation);
 	Relation	rd;
@@ -768,9 +768,21 @@ vac_update_relstats(Relation relation,
 		dirty = true;
 	}
 
-	/* If anything changed, write out the tuple. */
+	/*
+	 * If anything changed, write out the tuple. For ANALYZE, this change
+	 * needs to be transactional as this query can be run in a transaction
+	 * block.
+	 */
 	if (dirty)
-		heap_inplace_update(rd, ctup);
+	{
+		if (is_vacuum)
+		{
+			simple_heap_update(rd, &ctup->t_self, ctup);
+			CatalogUpdateIndexes(rd, ctup);
+		}
+		else
+			heap_inplace_update(rd, ctup);
+	}
 
 	heap_close(rd, RowExclusiveLock);
 }
diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c
index 5d6d031..3778d9d 100644
--- a/src/backend/commands/vacuumlazy.c
+++ b/src/backend/commands/vacuumlazy.c
@@ -309,7 +309,8 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt,
 						new_rel_allvisible,
 						vacrelstats->hasindex,
 						new_frozen_xid,
-						new_min_multi);
+						new_min_multi,
+						false);
 
 	/* report results to the stats collector, too */
 	new_live_tuples = new_rel_tuples - vacrelstats->new_dead_tuples;
@@ -1377,7 +1378,8 @@ lazy_cleanup_index(Relation indrel,
 							0,
 							false,
 							InvalidTransactionId,
-							InvalidMultiXactId);
+							InvalidMultiXactId,
+							false);
 
 	ereport(elevel,
 			(errmsg("index \"%s\" now contains %.0f row versions in %u pages",
diff --git a/src/include/commands/vacuum.h b/src/include/commands/vacuum.h
index d33552a..9781926 100644
--- a/src/include/commands/vacuum.h
+++ b/src/include/commands/vacuum.h
@@ -156,7 +156,8 @@ extern void vac_update_relstats(Relation relation,
 					BlockNumber num_all_visible_pages,
 					bool hasindex,
 					TransactionId frozenxid,
-					MultiXactId minmulti);
+					MultiXactId minmulti,
+					bool is_vacuum);
 extern void vacuum_set_xid_limits(Relation rel,
 					  int freeze_min_age, int freeze_table_age,
 					  int multixact_freeze_min_age,
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 10f45f2..f5ae511 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -2517,3 +2517,23 @@ ALTER TABLE logged1 SET UNLOGGED; -- silently do nothing
 DROP TABLE logged3;
 DROP TABLE logged2;
 DROP TABLE logged1;
+-- check presence of foreign key with transactional ANALYZE
+CREATE TABLE check_fk_presence_1 (id int PRIMARY KEY, t text);
+CREATE TABLE check_fk_presence_2 (id int REFERENCES check_fk_presence_1, t text);
+BEGIN;
+ALTER TABLE check_fk_presence_2 DROP CONSTRAINT check_fk_presence_2_id_fkey;
+COPY check_fk_presence_2 FROM stdin;
+ANALYZE check_fk_presence_2;
+ALTER TABLE check_fk_presence_2 ADD FOREIGN KEY (table1_fk) REFERENCES check_fk_presence_1 (id);
+ERROR:  column "table1_fk" referenced in foreign key constraint does not exist
+ROLLBACK;
+\d check_fk_presence_2
+Table "public.check_fk_presence_2"
+ Column |  Type   | Modifiers 
+--------+---------+-----------
+ id     | integer | 
+ t      | text    | 
+Foreign-key constraints:
+    "check_fk_presence_2_id_fkey" FOREIGN KEY (id) REFERENCES check_fk_presence_1(id)
+
+DROP TABLE check_fk_presence_1, check_fk_presence_2;
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index 12fd7c2..05d8226 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -1676,3 +1676,16 @@ ALTER TABLE logged1 SET UNLOGGED; -- silently do nothing
 DROP TABLE logged3;
 DROP TABLE logged2;
 DROP TABLE logged1;
+-- check presence of foreign key with transactional ANALYZE
+CREATE TABLE check_fk_presence_1 (id int PRIMARY KEY, t text);
+CREATE TABLE check_fk_presence_2 (id int REFERENCES check_fk_presence_1, t text);
+BEGIN;
+ALTER TABLE check_fk_presence_2 DROP CONSTRAINT check_fk_presence_2_id_fkey;
+COPY check_fk_presence_2 FROM stdin;
+1	test
+\.
+ANALYZE check_fk_presence_2;
+ALTER TABLE check_fk_presence_2 ADD FOREIGN KEY (table1_fk) REFERENCES check_fk_presence_1 (id);
+ROLLBACK;
+\d check_fk_presence_2
+DROP TABLE check_fk_presence_1, check_fk_presence_2;
-- 
2.1.2