MDEV-5619: CREATE OR REPLACE does not release MDL_EXCLUSIVE upon failure

mysql-test/r/create_or_replace.result:
  Added test of releasing of metadata locks
mysql-test/t/create_or_replace.test:
  Added test of releasing of metadata locks
sql/handler.h:
  Added marker if table was deleted as part of CREATE OR REPLACE
sql/sql_base.cc:
  Added Locked_tables_list::unlock_locked_table()
sql/sql_class.h:
  New prototypes
sql/sql_insert.cc:
  Unlock metadata locks for deleted table in case of error. Also do unlock tables if this was the only locked table.
sql/sql_table.cc:
  Unlock metadata locks for deleted table in case of error. Also do unlock tables if this was the only locked table.

1 files changed, 63 insertions, 0 deletions

diff --git a/mysql-test/r/create_or_replace.result b/mysql-test/r/create_or_replace.result
index 8f6ca01d34b..d8138bbc70d 100644
--- a/mysql-test/r/create_or_replace.result
+++ b/mysql-test/r/create_or_replace.result
@@ -247,6 +247,69 @@ a	i
 3	3
 drop table t1,t3;
 #
+# Test the meta data locks are freed properly
+#
+create database mysqltest2;
+drop table if exists test.t1,mysqltest2.t2;
+Warnings:
+Note	1051	Unknown table 'test.t1'
+Note	1051	Unknown table 'mysqltest2.t2'
+create table test.t1 (i int);
+create table mysqltest2.t2 like test.t1;
+lock table test.t1 write, mysqltest2.t2 write;
+select * from information_schema.metadata_lock_info;
+THREAD_ID	LOCK_MODE	LOCK_DURATION	LOCK_TYPE	TABLE_SCHEMA	TABLE_NAME
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Global read lock		
+3	MDL_SHARED_NO_READ_WRITE	MDL_EXPLICIT	Table metadata lock	test	t1
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Schema metadata lock	mysqltest2	
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Schema metadata lock	test	
+3	MDL_SHARED_NO_READ_WRITE	MDL_EXPLICIT	Table metadata lock	mysqltest2	t2
+create or replace table test.t1;
+ERROR 42000: A table must have at least 1 column
+show tables;
+Tables_in_test
+t2
+select * from information_schema.metadata_lock_info;
+THREAD_ID	LOCK_MODE	LOCK_DURATION	LOCK_TYPE	TABLE_SCHEMA	TABLE_NAME
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Global read lock		
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Schema metadata lock	mysqltest2	
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Schema metadata lock	test	
+3	MDL_SHARED_NO_READ_WRITE	MDL_EXPLICIT	Table metadata lock	mysqltest2	t2
+create or replace table mysqltest2.t2;
+ERROR 42000: A table must have at least 1 column
+select * from information_schema.metadata_lock_info;
+THREAD_ID	LOCK_MODE	LOCK_DURATION	LOCK_TYPE	TABLE_SCHEMA	TABLE_NAME
+create table t1 (i int);
+drop table t1;
+create table test.t1 (i int);
+create table mysqltest2.t2 like test.t1;
+lock table test.t1 write, mysqltest2.t2 write;
+select * from information_schema.metadata_lock_info;
+THREAD_ID	LOCK_MODE	LOCK_DURATION	LOCK_TYPE	TABLE_SCHEMA	TABLE_NAME
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Global read lock		
+3	MDL_SHARED_NO_READ_WRITE	MDL_EXPLICIT	Table metadata lock	test	t1
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Schema metadata lock	mysqltest2	
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Schema metadata lock	test	
+3	MDL_SHARED_NO_READ_WRITE	MDL_EXPLICIT	Table metadata lock	mysqltest2	t2
+create or replace table test.t1 (a int) select 1 as 'a', 2 as 'a';
+ERROR 42S21: Duplicate column name 'a'
+show tables;
+Tables_in_test
+t2
+select * from information_schema.metadata_lock_info;
+THREAD_ID	LOCK_MODE	LOCK_DURATION	LOCK_TYPE	TABLE_SCHEMA	TABLE_NAME
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Global read lock		
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Schema metadata lock	mysqltest2	
+3	MDL_INTENTION_EXCLUSIVE	MDL_EXPLICIT	Schema metadata lock	test	
+3	MDL_SHARED_NO_READ_WRITE	MDL_EXPLICIT	Table metadata lock	mysqltest2	t2
+create or replace table mysqltest2.t2 (a int) select 1 as 'a', 2 as 'a';
+ERROR 42S21: Duplicate column name 'a'
+select * from information_schema.metadata_lock_info;
+THREAD_ID	LOCK_MODE	LOCK_DURATION	LOCK_TYPE	TABLE_SCHEMA	TABLE_NAME
+create table t1 (i int);
+drop table t1;
+drop database mysqltest2;
+#
 # Testing CREATE .. LIKE
 #
 create or replace table t1 like t2;