Bug#36784795 Query rewrite plugin not working when server runs with

                          autocommit=OFF

Query rewrite plugin reload rules logic runs in an independent thread
created when a request is submitted. This thread runs the reload logic
and exits. When the server is in global autocommit OFF mode, the new
thread and its session will also run with autocommit OFF mode. At the
end of the reload execution, the code does a statement commit and exist.
Statement commits does not preserve the changes in autocommit OFF
mode. Due to this, after the thread exits, any table data changes done
will be lost.

Fix: Perform a transaction commit to ensure all changes are preserved
before exiting the session/thread.

Change-Id: Ib6f96873f90d99b2c53bb0157e91b160760b933e

Author: Ajo Robert

mysql-test/suite/query_rewrite_plugins/r/transactions.result

@@ -176,3 +176,25 @@ SET autocommit = DEFAULT;
 Warnings:
 Warning	1620	Plugin is busy and will be uninstalled on shutdown
 # Query rewrite plugin was queued for uninstalling.
+#
+# Bug#36784795 Query rewrite plugin not working when server runs with
+#              autocommit=OFF
+#
+# Query rewrite plugin was installed.
+SET GLOBAL autocommit = 0;
+SET SESSION autocommit = ON;
+DELETE FROM query_rewrite.rewrite_rules;
+INSERT INTO query_rewrite.rewrite_rules (pattern, replacement)
+VALUES('SELECT ?', 'SELECT ? + 1');
+SELECT * FROM query_rewrite.rewrite_rules;
+id	pattern	pattern_database	replacement	enabled	message	pattern_digest	normalized_pattern
+1	SELECT ?	NULL	SELECT ? + 1	YES	NULL	NULL	NULL
+CALL query_rewrite.flush_rewrite_rules();
+SELECT * FROM query_rewrite.rewrite_rules;
+id	pattern	pattern_database	replacement	enabled	message	pattern_digest	normalized_pattern
+1	SELECT ?	NULL	SELECT ? + 1	YES	NULL	d1b44b0c19af710b5a679907e284acd2ddc285201794bc69a2389d77baedddae	select ?
+SET GLOBAL autocommit = DEFAULT;
+SET SESSION autocommit = DEFAULT;
+Warnings:
+Warning	1620	Plugin is busy and will be uninstalled on shutdown
+# Query rewrite plugin was queued for uninstalling.

mysql-test/suite/query_rewrite_plugins/t/transactions.test

@@ -131,5 +131,25 @@ SELECT load_rewrite_rules();
 SELECT 'Rewrite me';
 
 SET autocommit = DEFAULT;
+--source suite/query_rewrite_plugins/include/uninstall_rewriter.inc
+--source include/disconnect_connections.inc
+
+--echo #
+--echo # Bug#36784795 Query rewrite plugin not working when server runs with
+--echo #              autocommit=OFF
+--echo #
+--source suite/query_rewrite_plugins/include/install_rewriter_with_optional_columns.inc
+
+SET GLOBAL autocommit = 0;
+SET SESSION autocommit = ON;
+#Session autocommit is not needed to set to OFF for this test.
+DELETE FROM query_rewrite.rewrite_rules;
+INSERT INTO query_rewrite.rewrite_rules (pattern, replacement)
+        VALUES('SELECT ?', 'SELECT ? + 1');
+SELECT * FROM query_rewrite.rewrite_rules;
+CALL query_rewrite.flush_rewrite_rules();
+SELECT * FROM query_rewrite.rewrite_rules;
+SET GLOBAL autocommit = DEFAULT;
+SET SESSION autocommit = DEFAULT;
 
 --source suite/query_rewrite_plugins/include/uninstall_rewriter.inc

sql/parser_service.cc

@@ -183,6 +183,7 @@ void *parser_service_start_routine(void *arg) {
     (tt->m_fun)(tt->m_arg);
 
     trans_commit_stmt(thd);
+    trans_commit(thd);
     close_thread_tables(thd);
     thd->mdl_context.release_transactional_locks();
     close_mysql_tables(thd);