Bug #11765416 (former 58381)

FAILED DROP DATABASE CAN BREAK STATEMENT BASED REPLICATION

The first phase of DROP DATABASE is to delete the tables in the database.
If deletion of one or more of the tables fail (e.g. due to a FOREIGN KEY
constraint), DROP DATABASE will be aborted. However, some tables could
still have been deleted. The problem was that nothing would be written
to the binary log in this case, so any slaves would not delete these tables.
Therefore the master and the slaves would get out of sync.

This patch fixes the problem by making sure that DROP TABLE is written
to the binary log for the tables that were in fact deleted by the failed
DROP DATABASE statement.

Test case added to binlog.binlog_database.test.

3 files changed, 108 insertions, 8 deletions

diff --git a/mysql-test/extra/binlog_tests/database.test b/mysql-test/extra/binlog_tests/database.test
index 326ecedb60e..d071415bf65 100644
--- a/mysql-test/extra/binlog_tests/database.test
+++ b/mysql-test/extra/binlog_tests/database.test
@@ -30,3 +30,30 @@ drop table tt1, t1;
 source include/show_binlog_events.inc;
 
 FLUSH STATUS;
+
+
+--echo #
+--echo # Bug#11765416 58381: FAILED DROP DATABASE CAN BREAK STATEMENT
+--echo #              BASED REPLICATION
+--echo #
+
+--disable_warnings
+DROP DATABASE IF EXISTS db1;
+DROP TABLE IF EXISTS t3;
+--enable_warnings
+
+CREATE DATABASE db1;
+CREATE TABLE db1.t1 (a INT);
+CREATE TABLE db1.t2 (b INT, KEY(b)) engine=innodb;
+CREATE TABLE t3 (a INT, KEY (a), FOREIGN KEY(a) REFERENCES db1.t2(b))
+  engine=innodb;
+RESET MASTER;
+
+--error ER_ROW_IS_REFERENCED
+DROP DATABASE db1;                      # Fails because of the fk
+SHOW TABLES FROM db1;                   # t1 was dropped, t2 remains
+--source include/show_binlog_events.inc # Check that the binlog drops t1
+
+# Cleanup
+DROP TABLE t3;
+DROP DATABASE db1;
diff --git a/mysql-test/suite/binlog/r/binlog_database.result b/mysql-test/suite/binlog/r/binlog_database.result
index b6299f9a940..0eaed3c97d7 100644
--- a/mysql-test/suite/binlog/r/binlog_database.result
+++ b/mysql-test/suite/binlog/r/binlog_database.result
@@ -39,6 +39,28 @@ master-bin.000001	#	Query	#	#	COMMIT
 master-bin.000001	#	Query	#	#	use `test`; DROP TEMPORARY TABLE `tt1` /* generated by server */
 master-bin.000001	#	Query	#	#	use `test`; DROP TABLE `t1` /* generated by server */
 FLUSH STATUS;
+#
+# Bug#11765416 58381: FAILED DROP DATABASE CAN BREAK STATEMENT
+#              BASED REPLICATION
+#
+DROP DATABASE IF EXISTS db1;
+DROP TABLE IF EXISTS t3;
+CREATE DATABASE db1;
+CREATE TABLE db1.t1 (a INT);
+CREATE TABLE db1.t2 (b INT, KEY(b)) engine=innodb;
+CREATE TABLE t3 (a INT, KEY (a), FOREIGN KEY(a) REFERENCES db1.t2(b))
+engine=innodb;
+RESET MASTER;
+DROP DATABASE db1;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails
+SHOW TABLES FROM db1;
+Tables_in_db1
+t2
+show binlog events from <binlog_start>;
+Log_name	Pos	Event_type	Server_id	End_log_pos	Info
+master-bin.000001	#	Query	#	#	use `db1`; drop table `t1`
+DROP TABLE t3;
+DROP DATABASE db1;
 set binlog_format=mixed;
 reset master;
 create database testing_1;
@@ -80,6 +102,28 @@ master-bin.000001	#	Query	#	#	COMMIT
 master-bin.000001	#	Query	#	#	use `test`; DROP TEMPORARY TABLE `tt1` /* generated by server */
 master-bin.000001	#	Query	#	#	use `test`; DROP TABLE `t1` /* generated by server */
 FLUSH STATUS;
+#
+# Bug#11765416 58381: FAILED DROP DATABASE CAN BREAK STATEMENT
+#              BASED REPLICATION
+#
+DROP DATABASE IF EXISTS db1;
+DROP TABLE IF EXISTS t3;
+CREATE DATABASE db1;
+CREATE TABLE db1.t1 (a INT);
+CREATE TABLE db1.t2 (b INT, KEY(b)) engine=innodb;
+CREATE TABLE t3 (a INT, KEY (a), FOREIGN KEY(a) REFERENCES db1.t2(b))
+engine=innodb;
+RESET MASTER;
+DROP DATABASE db1;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails
+SHOW TABLES FROM db1;
+Tables_in_db1
+t2
+show binlog events from <binlog_start>;
+Log_name	Pos	Event_type	Server_id	End_log_pos	Info
+master-bin.000001	#	Query	#	#	use `db1`; drop table `t1`
+DROP TABLE t3;
+DROP DATABASE db1;
 set binlog_format=row;
 reset master;
 create database testing_1;
@@ -122,6 +166,28 @@ master-bin.000001	#	Query	#	#	COMMIT
 master-bin.000001	#	Query	#	#	use `test`; DROP TEMPORARY TABLE IF EXISTS `tt1` /* generated by server */
 master-bin.000001	#	Query	#	#	use `test`; DROP TABLE `t1` /* generated by server */
 FLUSH STATUS;
+#
+# Bug#11765416 58381: FAILED DROP DATABASE CAN BREAK STATEMENT
+#              BASED REPLICATION
+#
+DROP DATABASE IF EXISTS db1;
+DROP TABLE IF EXISTS t3;
+CREATE DATABASE db1;
+CREATE TABLE db1.t1 (a INT);
+CREATE TABLE db1.t2 (b INT, KEY(b)) engine=innodb;
+CREATE TABLE t3 (a INT, KEY (a), FOREIGN KEY(a) REFERENCES db1.t2(b))
+engine=innodb;
+RESET MASTER;
+DROP DATABASE db1;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails
+SHOW TABLES FROM db1;
+Tables_in_db1
+t2
+show binlog events from <binlog_start>;
+Log_name	Pos	Event_type	Server_id	End_log_pos	Info
+master-bin.000001	#	Query	#	#	use `db1`; drop table `t1`
+DROP TABLE t3;
+DROP DATABASE db1;
 show databases;
 Database
 information_schema
diff --git a/sql/sql_db.cc b/sql/sql_db.cc
index 38f39ec0be7..665bcbbbe9f 100644
--- a/sql/sql_db.cc
+++ b/sql/sql_db.cc
@@ -1,4 +1,4 @@
-/* Copyright (C) 2000-2003 MySQL AB, 2008-2009 Sun Microsystems, Inc
+/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -833,12 +833,9 @@ bool mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
   }
 
   thd->push_internal_handler(&err_handler);
-  if (thd->killed ||
-      (tables && mysql_rm_table_no_locks(thd, tables, true, false, true, true)))
-  {
-    tables= NULL;
-  }
-  else
+  if (!thd->killed &&
+      !(tables &&
+        mysql_rm_table_no_locks(thd, tables, true, false, true, true)))
   {
     /*
       We temporarily disable the binary log while dropping the objects
@@ -923,7 +920,7 @@ update_binlog:
     thd->server_status|= SERVER_STATUS_DB_DROPPED;
     my_ok(thd, deleted_tables);
   }
-  else if (mysql_bin_log.is_open())
+  else if (mysql_bin_log.is_open() && !silent)
   {
     char *query, *query_pos, *query_end, *query_data_start;
     TABLE_LIST *tbl;
@@ -938,6 +935,16 @@ update_binlog:
     for (tbl= tables; tbl; tbl= tbl->next_local)
     {
       uint tbl_name_len;
+      bool exists;
+
+      // Only write drop table to the binlog for tables that no longer exist.
+      if (check_if_table_exists(thd, tbl, &exists))
+      {
+        error= true;
+        goto exit;
+      }
+      if (exists)
+        continue;
 
       /* 3 for the quotes and the comma*/
       tbl_name_len= strlen(tbl->table_name) + 3;