BUG#20574550 MAIN.MERGE TEST CASE FAILS IF BINLOG_FORMAT=ROW

The main.merge test case was failing when tested using row based
binlog format.

While analyzing the issue it was found the following issues:

a) The server is calling binlog related code even when a statement will
   not be binlogged;
b) The child table list was not present into table structure by the time
   to generate the create table statement;
c) The tables in the child table list will not be opened yet when
   generating table create info using row based replication;
d) CREATE TABLE LIKE TEMP_TABLE does not preserve original table storage
   engine when using row based replication;

This patch addressed all above issues.

@ sql/sql_class.h

Added a function to determine if the binary log is disabled to
  the current session. This is related with issue (a) above.

@ sql/sql_table.cc

Added code to skip binary logging related code if the statement
  will not be binlogged. This is related with issue (a) above.

Added code to add the children to the query list of the table that
  will have its CREATE TABLE generated. This is related with issue (b)
  above.

Added code to force the storage engine to be generated into the
  CREATE TABLE. This is related with issue (d) above.

@ storage/myisammrg/ha_myisammrg.cc

Added a test to skip a table getting info about a child table if the
  child table is not opened. This is related to issue (c) above.

mysql-test/suite/binlog/r/binlog_row_binlog.result

@@ -1203,7 +1203,7 @@ master-bin.000001	#	Query	#	#	use `test`; CREATE TABLE IF NOT EXISTS `t2` (
 master-bin.000001	#	Query	#	#	COMMIT
 master-bin.000001	#	Query	#	#	use `test`; CREATE TABLE IF NOT EXISTS `t3` (
   `a` int(11) DEFAULT NULL
-)
+) ENGINE=MyISAM
 master-bin.000001	#	Query	#	#	BEGIN
 master-bin.000001	#	Table_map	#	#	table_id: # (mysql.user)
 master-bin.000001	#	Write_rows	#	#	table_id: # flags: STMT_END_F
@@ -1238,7 +1238,7 @@ master-bin.000001	#	Query	#	#	use `test`; CREATE TABLE IF NOT EXISTS `t2` (
 master-bin.000001	#	Query	#	#	COMMIT
 master-bin.000001	#	Query	#	#	use `test`; CREATE TABLE IF NOT EXISTS `t3` (
   `a` int(11) DEFAULT NULL
-)
+) ENGINE=MyISAM
 master-bin.000001	#	Query	#	#	BEGIN
 master-bin.000001	#	Table_map	#	#	table_id: # (mysql.user)
 master-bin.000001	#	Write_rows	#	#	table_id: # flags: STMT_END_F

mysql-test/suite/rpl/r/rpl_row_merge_engine.result

@@ -4,8 +4,9 @@ CREATE TABLE t1 (a int) ENGINE=MyISAM;
 CREATE TABLE t2 (a int) ENGINE=MyISAM;
 INSERT INTO t1 VALUES (1), (2), (3);
 INSERT INTO t2 VALUES (4), (5), (6);
-CREATE TABLE IF NOT EXISTS t1_merge LIKE t1;
-ALTER TABLE t1_merge ENGINE=MERGE UNION (t2, t1);
+CREATE TEMPORARY TABLE IF NOT EXISTS tt1_merge LIKE t1;
+ALTER TABLE tt1_merge ENGINE=MERGE UNION (t2, t1);
+CREATE TABLE t1_merge LIKE tt1_merge;
 include/diff_tables.inc [master:test.t1, slave:test.t1]
 include/diff_tables.inc [master:test.t2, slave:test.t2]
 UPDATE t1_merge SET a=10 WHERE a=1;

mysql-test/suite/rpl/r/rpl_tmp_table_and_DDL.result

@@ -192,4 +192,14 @@ DROP FUNCTION f2;
 DROP PROCEDURE p2;
 DROP EVENT e2;
 DROP TABLE t1, t2;
+CREATE TEMPORARY TABLE temp_t1 (c1 INT) ENGINE=InnoDB;
+CREATE TEMPORARY TABLE temp_t2 (c1 INT) ENGINE=MyISAM;
+CREATE TABLE t1 LIKE temp_t1;
+CREATE TABLE t2 LIKE temp_t2;
+include/assert.inc ["t1 on master and temp_t1 have the same storage engine"]
+include/assert.inc ["t2 on master and temp_t2 have the same storage engine"]
+include/assert.inc ["t1 on slave and temp_t1 have the same storage engine"]
+include/assert.inc ["t2 on slave and temp_t2 have the same storage engine"]
+DROP TEMPORARY TABLE temp_t1, temp_t2;
+DROP TABLE t1, t2;
 include/rpl_end.inc

mysql-test/suite/rpl/t/rpl_row_merge_engine.test

@@ -20,8 +20,10 @@ CREATE TABLE t1 (a int) ENGINE=MyISAM;
 CREATE TABLE t2 (a int) ENGINE=MyISAM;
 INSERT INTO t1 VALUES (1), (2), (3);
 INSERT INTO t2 VALUES (4), (5), (6);
-CREATE TABLE IF NOT EXISTS t1_merge LIKE t1;
-ALTER TABLE t1_merge ENGINE=MERGE UNION (t2, t1);
+# Changed a little to check also an issue reported on BUG#20574550
+CREATE TEMPORARY TABLE IF NOT EXISTS tt1_merge LIKE t1;
+ALTER TABLE tt1_merge ENGINE=MERGE UNION (t2, t1);
+CREATE TABLE t1_merge LIKE tt1_merge;
 
 --sync_slave_with_master
 

mysql-test/suite/rpl/t/rpl_tmp_table_and_DDL.test

@@ -166,4 +166,55 @@ DROP PROCEDURE p2;
 DROP EVENT e2;
 DROP TABLE t1, t2;
 
+--sync_slave_with_master
+#
+# BUG#20574550
+# CREATE TABLE LIKE <TEMP_TABLE> does not preserve original table storage
+# engine when using row based replication
+#
+--connection master
+
+# Define temp_t1 and temp_t2 storage engines
+--let $engine_temp_t1= InnoDB
+--let $engine_temp_t2= MyISAM
+
+# Create the two temporary tables
+--eval CREATE TEMPORARY TABLE temp_t1 (c1 INT) ENGINE=$engine_temp_t1
+--eval CREATE TEMPORARY TABLE temp_t2 (c1 INT) ENGINE=$engine_temp_t2
+
+# Create t1 and t2 based on temporary tables
+CREATE TABLE t1 LIKE temp_t1;
+CREATE TABLE t2 LIKE temp_t2;
+--sync_slave_with_master
+
+# On master
+--connection master
+# Assert that t1 and t2 have the same storage engines as temp_t1 and temp_t2
+--let $engine_t1= query_get_value(SHOW TABLE STATUS WHERE Name='t1', Engine, 1)
+--let $assert_cond= "$engine_t1" = "$engine_temp_t1"
+--let $assert_text= "t1 on master and temp_t1 have the same storage engine"
+--source include/assert.inc
+
+--let $engine_t2= query_get_value(SHOW TABLE STATUS WHERE Name='t2', Engine, 1)
+--let $assert_cond= "$engine_t2" = "$engine_temp_t2"
+--let $assert_text= "t2 on master and temp_t2 have the same storage engine"
+--source include/assert.inc
+
+# On slave
+--connection slave
+# Assert that t1 and t2 have the same storage engines as temp_t1 and temp_t2
+--let $engine_t1= query_get_value(SHOW TABLE STATUS WHERE Name='t1', Engine, 1)
+--let $assert_cond= "$engine_t1" = "$engine_temp_t1"
+--let $assert_text= "t1 on slave and temp_t1 have the same storage engine"
+--source include/assert.inc
+
+--let $engine_t2= query_get_value(SHOW TABLE STATUS WHERE Name='t2', Engine, 1)
+--let $assert_cond= "$engine_t2" = "$engine_temp_t2"
+--let $assert_text= "t2 on slave and temp_t2 have the same storage engine"
+--source include/assert.inc
+
+# Cleanup
+--connection master
+DROP TEMPORARY TABLE temp_t1, temp_t2;
+DROP TABLE t1, t2;
 --source include/rpl_end.inc

sql/sql_class.h

-/* Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2000, 2016, 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
@@ -1662,6 +1662,18 @@ class THD :public Statement,
                 current_stmt_binlog_format == BINLOG_FORMAT_ROW);
     return current_stmt_binlog_format == BINLOG_FORMAT_ROW;
   }
+  /**
+    Determine if binlogging is disabled for this session
+    @retval 0 if the current statement binlogging is disabled
+              (could be because of binlog closed/binlog option
+               is set to false).
+    @retval 1 if the current statement will be binlogged
+  */
+  inline bool is_current_stmt_binlog_disabled() const
+  {
+    return (!(variables.option_bits & OPTION_BIN_LOG) ||
+            !mysql_bin_log.is_open());
+  }
 
 private:
   /**

sql/sql_table.cc

 /*
-   Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2000, 2016, 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
@@ -4709,7 +4709,8 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table, TABLE_LIST* src_table,
   /*
     We have to write the query before we unlock the tables.
   */
-  if (thd->is_current_stmt_binlog_format_row())
+  if (!thd->is_current_stmt_binlog_disabled() &&
+      thd->is_current_stmt_binlog_format_row())
   {
     /*
        Since temporary tables are not replicated under row-based
@@ -4751,6 +4752,21 @@ bool mysql_create_like_table(THD* thd, TABLE_LIST* table, TABLE_LIST* src_table,
           if (open_table(thd, table, thd->mem_root, &ot_ctx))
             goto err;
 
+          /*
+            After opening a MERGE table add the children to the query list of
+            tables, so that children tables info can be used on "CREATE TABLE"
+            statement generation by the binary log.
+            Note that placeholders don't have the handler open.
+          */
+          if (table->table->file->extra(HA_EXTRA_ADD_CHILDREN_LIST))
+            goto err;
+
+          /*
+            As the reference table is temporary and may not exist on slave, we must
+            force the ENGINE to be present into CREATE TABLE.
+          */
+          create_info->used_fields|= HA_CREATE_USED_ENGINE;
+
           int result __attribute__((unused))=
             store_create_info(thd, table, &query,
                               create_info, TRUE /* show_database */);

storage/myisammrg/ha_myisammrg.cc

-/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2000, 2016, 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
@@ -1481,6 +1481,8 @@ void ha_myisammrg::update_create_info(HA_CREATE_INFO *create_info)
 	 open_table != file->end_table ;
 	 open_table++)
     {
+      if (!open_table->table)
+        continue;
       TABLE_LIST *ptr;
       LEX_STRING db, name;
       LINT_INIT(db.str);