MDEV-9084 Calling a stored function from a nested select from temporary table...
MDEV-9084 Calling a stored function from a nested select from temporary table causes unpredictable behavior Cherry-pick: f4a0af070ce49abae60040f6f32e1074309c27fb Author: Dmitry Lenev <dmitry.lenev@oracle.com> Date: Mon Jul 25 16:06:52 2016 +0300 Fix for bug #16672723 "CAN'T FIND TEMPORARY TABLE". Attempt to execute prepared CREATE TABLE SELECT statement which used temporary table in the subquery in FROM clause and stored function failed with unwarranted ER_NO_SUCH_TABLE error. The same happened when such statement was used in stored procedure and this procedure was re-executed. The problem occurred because execution of such prepared statement/its re-execution as part of stored procedure incorrectly set Query_table_list::query_tables_own_last marker, indicating the last table which is directly used by statement. As result temporary table used in the subquery was treated as indirectly used/belonging to prelocking list and was not pre-opened by open_temporary_tables() call before statement execution. Thus causing ER_NO_SUCH_TABLE errors since our code assumes that temporary tables need to be correctly pre-opened before statement execution. This problem became visible only in version 5.6 after patches related to bug 11746602/27480 "EXTEND CREATE TEMPORARY TABLES PRIVILEGE TO ALLOW TEMP TABLE OPERATIONS" since they have introduced pre-opening of temporary tables for statements. Incorrect setting of Query_table_list::query_tables_own_last happened in LEX::first_lists_tables_same() method which is called by CREATE TABLE SELECT implementation as part of LEX::unlink_first_table(), which temporary excludes table list element for table being created from the query table list before handling SELECT part. LEX::first_lists_tables_same() tries to ensure that global table list of the statement starts with the first table list element from the first statement select. To do this it moves such table list element to the head of the global table list. If this table happens to be last directly-used table for the statement, query_tables_own_last marker is pointing to it. Since this marker was not updated when table list element was moved we ended up with all tables except the first table separated by it as if they were not directly used by statement (i.e. belonged to prelocked tables list). This fix changes code of LEX::first_lists_tables_same() to update query_tables_own_last marker in cases when it points to the table being moved. It is set to the table which precedes table being moved in this case.
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