Merge 10.2 into 10.3

21 files changed, 123 insertions, 83 deletions

diff --git a/sql/item.h b/sql/item.h
index c3675adb74f..f161b55e950 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -816,6 +816,11 @@ public:
   void set_name_no_truncate(THD *thd, const char *str, uint length,
                             CHARSET_INFO *cs);
   void init_make_send_field(Send_field *tmp_field,enum enum_field_types type);
+  void share_name_with(const Item *item)
+  {
+    name= item->name;
+    is_autogenerated_name= item->is_autogenerated_name;
+  }
   virtual void cleanup();
   virtual void make_send_field(THD *thd, Send_field *field);
 
diff --git a/sql/log_event.cc b/sql/log_event.cc
index 4792a2c9f0e..c7fc6a04f64 100644
--- a/sql/log_event.cc
+++ b/sql/log_event.cc
@@ -7528,10 +7528,10 @@ error:
   if (thd->transaction_rollback_request)
   {
     trans_rollback_implicit(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   }
   else if (! thd->in_multi_stmt_transaction_mode())
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   else
     thd->mdl_context.release_statement_locks();
 
@@ -9008,7 +9008,7 @@ int Xid_log_event::do_apply_event(rpl_group_info *rgi)
                     "COMMIT /* implicit, from Xid_log_event */");
   thd->variables.option_bits&= ~OPTION_GTID_BEGIN;
   res= trans_commit(thd); /* Automatically rolls back on error. */
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
 
 #ifdef WITH_WSREP
   if (WSREP(thd)) mysql_mutex_lock(&thd->LOCK_thd_data);
diff --git a/sql/mdl.cc b/sql/mdl.cc
index 8d6780671d1..952648ce2d8 100644
--- a/sql/mdl.cc
+++ b/sql/mdl.cc
@@ -2845,6 +2845,9 @@ void MDL_context::rollback_to_savepoint(const MDL_savepoint &mdl_savepoint)
 void MDL_context::release_transactional_locks()
 {
   DBUG_ENTER("MDL_context::release_transactional_locks");
+  /* Fail if there are active transactions */
+  DBUG_ASSERT(!(current_thd->server_status &
+                (SERVER_STATUS_IN_TRANS | SERVER_STATUS_IN_TRANS_READONLY)));
   release_locks_stored_before(MDL_STATEMENT, NULL);
   release_locks_stored_before(MDL_TRANSACTION, NULL);
   DBUG_VOID_RETURN;
diff --git a/sql/rpl_gtid.cc b/sql/rpl_gtid.cc
index a8b39d6d15b..8408025d389 100644
--- a/sql/rpl_gtid.cc
+++ b/sql/rpl_gtid.cc
@@ -433,7 +433,7 @@ rpl_slave_state::truncate_state_table(THD *thd)
       close_thread_tables(thd);
       ha_commit_trans(thd, TRUE);
     }
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   }
 
   reenable_binlog(thd);
@@ -864,7 +864,7 @@ end:
     }
     else
     {
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
 #ifdef HAVE_REPLICATION
       rpl_group_info::pending_gtid_deletes_free(delete_list);
 #endif
diff --git a/sql/rpl_injector.cc b/sql/rpl_injector.cc
index 597a357e4e2..442d28fceb3 100644
--- a/sql/rpl_injector.cc
+++ b/sql/rpl_injector.cc
@@ -68,34 +68,34 @@ injector::transaction::~transaction()
  */
 int injector::transaction::commit()
 {
-   DBUG_ENTER("injector::transaction::commit()");
-   int error= m_thd->binlog_flush_pending_rows_event(true);
-   /*
-     Cluster replication does not preserve statement or
-     transaction boundaries of the master.  Instead, a new
-     transaction on replication slave is started when a new GCI
-     (global checkpoint identifier) is issued, and is committed
-     when the last event of the check point has been received and
-     processed. This ensures consistency of each cluster in
-     cluster replication, and there is no requirement for stronger
-     consistency: MySQL replication is asynchronous with other
-     engines as well.
-
-     A practical consequence of that is that row level replication
-     stream passed through the injector thread never contains
-     COMMIT events.
-     Here we should preserve the server invariant that there is no
-     outstanding statement transaction when the normal transaction
-     is committed by committing the statement transaction
-     explicitly.
-   */
-   trans_commit_stmt(m_thd);
-   if (!trans_commit(m_thd))
-   {
-     close_thread_tables(m_thd);
-     m_thd->mdl_context.release_transactional_locks();
-   }
-   DBUG_RETURN(error);
+  DBUG_ENTER("injector::transaction::commit()");
+  int error= m_thd->binlog_flush_pending_rows_event(true);
+  /*
+    Cluster replication does not preserve statement or
+    transaction boundaries of the master.  Instead, a new
+    transaction on replication slave is started when a new GCI
+    (global checkpoint identifier) is issued, and is committed
+    when the last event of the check point has been received and
+    processed. This ensures consistency of each cluster in
+    cluster replication, and there is no requirement for stronger
+    consistency: MySQL replication is asynchronous with other
+    engines as well.
+
+    A practical consequence of that is that row level replication
+    stream passed through the injector thread never contains
+    COMMIT events.
+    Here we should preserve the server invariant that there is no
+    outstanding statement transaction when the normal transaction
+    is committed by committing the statement transaction
+    explicitly.
+  */
+  trans_commit_stmt(m_thd);
+  if (!trans_commit(m_thd))
+  {
+    close_thread_tables(m_thd);
+    m_thd->release_transactional_locks();
+  }
+  DBUG_RETURN(error);
 }
 
 
diff --git a/sql/rpl_rli.cc b/sql/rpl_rli.cc
index 7bc38d28961..5e6837c32c7 100644
--- a/sql/rpl_rli.cc
+++ b/sql/rpl_rli.cc
@@ -1998,7 +1998,7 @@ end:
     ha_commit_trans(thd, FALSE);
     ha_commit_trans(thd, TRUE);
     close_thread_tables(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   }
 
   return err;
@@ -2288,7 +2288,7 @@ void rpl_group_info::cleanup_context(THD *thd, bool error)
 
   if (unlikely(error))
   {
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
 
     if (thd == rli->sql_driver_thd)
     {
@@ -2402,10 +2402,10 @@ void rpl_group_info::slave_close_thread_tables(THD *thd)
   if (thd->transaction_rollback_request)
   {
     trans_rollback_implicit(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   }
   else if (! thd->in_multi_stmt_transaction_mode())
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   else
     thd->mdl_context.release_statement_locks();
 
diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index 59a304deb99..bd41de78c9a 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -2346,10 +2346,10 @@ sp_head::execute_procedure(THD *thd, List<Item> *args)
       if (thd->transaction_rollback_request)
       {
         trans_rollback_implicit(thd);
-        thd->mdl_context.release_transactional_locks();
+        thd->release_transactional_locks();
       }
       else if (! thd->in_multi_stmt_transaction_mode())
-        thd->mdl_context.release_transactional_locks();
+        thd->release_transactional_locks();
       else
         thd->mdl_context.release_statement_locks();
     }
@@ -3457,10 +3457,10 @@ sp_lex_keeper::reset_lex_and_exec_core(THD *thd, uint *nextp,
       if (thd->transaction_rollback_request)
       {
         trans_rollback_implicit(thd);
-        thd->mdl_context.release_transactional_locks();
+        thd->release_transactional_locks();
       }
       else if (! thd->in_multi_stmt_transaction_mode())
-        thd->mdl_context.release_transactional_locks();
+        thd->release_transactional_locks();
       else
         thd->mdl_context.release_statement_locks();
     }
diff --git a/sql/sql_acl.cc b/sql/sql_acl.cc
index c4b8d41d04c..205ab7f5974 100644
--- a/sql/sql_acl.cc
+++ b/sql/sql_acl.cc
@@ -8938,6 +8938,8 @@ static bool show_global_privileges(THD *thd, ACL_USER_BASE *acl_entry,
     add_user_parameters(thd, &global, (ACL_USER *)acl_entry,
                         (want_access & GRANT_ACL));
 
+  else if (want_access & GRANT_ACL)
+    global.append(STRING_WITH_LEN(" WITH GRANT OPTION"));
   protocol->prepare_for_resend();
   protocol->store(global.ptr(),global.length(),global.charset());
   if (protocol->write())
diff --git a/sql/sql_admin.cc b/sql/sql_admin.cc
index 8e956eb0f8c..b5c8514c302 100644
--- a/sql/sql_admin.cc
+++ b/sql/sql_admin.cc
@@ -1,5 +1,5 @@
 /* Copyright (c) 2010, 2015, Oracle and/or its affiliates.
-   Copyright (c) 2011, 2019, MariaDB
+   Copyright (c) 2011, 2020, MariaDB
 
    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
@@ -43,7 +43,7 @@ static bool admin_recreate_table(THD *thd, TABLE_LIST *table_list)
   trans_rollback_stmt(thd);
   trans_rollback(thd);
   close_thread_tables(thd);
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
 
   /*
     table_list->table has been closed and freed. Do not reference
@@ -116,7 +116,7 @@ static int prepare_for_repair(THD *thd, TABLE_LIST *table_list,
       acquire the exclusive lock to satisfy MDL asserts and avoid
       deadlocks.
     */
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
     /*
       Attempt to do full-blown table open in mysql_admin_table() has failed.
       Let us try to open at least a .FRM for this table.
@@ -285,7 +285,7 @@ end:
   }
   /* In case of a temporary table there will be no metadata lock. */
   if (unlikely(error) && has_mdl_lock)
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
 
   DBUG_RETURN(error);
 }
@@ -563,7 +563,7 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
       trans_rollback(thd);
       close_thread_tables(thd);
       table->table= NULL;
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       table->mdl_request.init(MDL_key::TABLE, table->db.str, table->table_name.str,
                               MDL_SHARED_NO_READ_WRITE, MDL_TRANSACTION);
     }
@@ -623,7 +623,7 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
         trans_rollback_stmt(thd);
         trans_rollback(thd);
         close_thread_tables(thd);
-        thd->mdl_context.release_transactional_locks();
+        thd->release_transactional_locks();
         DBUG_PRINT("admin", ("simple error, admin next table"));
         continue;
       case -1:           // error, message could be written to net
@@ -690,7 +690,7 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
       trans_commit_stmt(thd);
       trans_commit(thd);
       close_thread_tables(thd);
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       lex->reset_query_tables_list(FALSE);
       /*
         Restore Query_tables_list::sql_command value to make statement
@@ -823,7 +823,7 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
       thd->open_options|= extra_open_options;
       close_thread_tables(thd);
       table->table= NULL;
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       table->mdl_request.init(MDL_key::TABLE, table->db.str, table->table_name.str,
                               MDL_SHARED_NO_READ_WRITE, MDL_TRANSACTION);
       table->mdl_request.set_type(MDL_SHARED_READ);
@@ -1055,7 +1055,7 @@ send_result_message:
       trans_commit_stmt(thd);
       trans_commit(thd);
       close_thread_tables(thd);
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       /* Clear references to TABLE and MDL_ticket after releasing them. */
       table->mdl_request.ticket= NULL;
 
@@ -1208,7 +1208,7 @@ send_result_message:
         goto err;
     }
     close_thread_tables(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
 
     /*
       If it is CHECK TABLE v1, v2, v3, and v1, v2, v3 are views, we will run
@@ -1246,7 +1246,7 @@ err:
     table->table= 0;
   }
   close_thread_tables(thd);			// Shouldn't be needed
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
   thd->resume_subsequent_commits(suspended_wfc);
   DBUG_RETURN(TRUE);
 }
diff --git a/sql/sql_base.cc b/sql/sql_base.cc
index ada1a7cd36a..f7d93bec0df 100644
--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -8975,7 +8975,7 @@ close_mysql_tables(THD *thd)
   if (! thd->in_sub_stmt)
     trans_commit_stmt(thd);
   close_thread_tables(thd);
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
 }
 
 /*
diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index 869ce72f861..a7057e3d5d4 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -4739,7 +4739,7 @@ void destroy_thd(MYSQL_THD thd)
 void reset_thd(MYSQL_THD thd)
 {
   close_thread_tables(thd);
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
   thd->free_items();
   free_root(thd->mem_root, MYF(MY_KEEP_PREALLOC));
 }
diff --git a/sql/sql_class.h b/sql/sql_class.h
index 537bfe037d4..33342b16aad 100644
--- a/sql/sql_class.h
+++ b/sql/sql_class.h
@@ -4469,6 +4469,13 @@ public:
     locked_tables_mode= mode_arg;
   }
   void leave_locked_tables_mode();
+  /* Relesae transactional locks if there are no active transactions */
+  void release_transactional_locks()
+  {
+    if (!(server_status &
+          (SERVER_STATUS_IN_TRANS | SERVER_STATUS_IN_TRANS_READONLY)))
+      mdl_context.release_transactional_locks();
+  }
   int decide_logging_format(TABLE_LIST *tables);
   /*
    In Some cases when decide_logging_format is called it does not have all
diff --git a/sql/sql_derived.cc b/sql/sql_derived.cc
index 11d3a13b8b9..eb840e02a27 100644
--- a/sql/sql_derived.cc
+++ b/sql/sql_derived.cc
@@ -1271,7 +1271,8 @@ bool pushdown_cond_for_derived(THD *thd, Item *cond, TABLE_LIST *derived)
     DBUG_RETURN(false);
 
   st_select_lex_unit *unit= derived->get_unit();
-  st_select_lex *sl= unit->first_select();
+  st_select_lex *first_sl= unit->first_select();
+  st_select_lex *sl= first_sl;
 
   if (derived->prohibit_cond_pushdown)
     DBUG_RETURN(false);
@@ -1419,7 +1420,24 @@ bool pushdown_cond_for_derived(THD *thd, Item *cond, TABLE_LIST *derived)
       if (!extracted_cond_copy)
         continue;
     }
-    
+
+    /*
+      Rename the columns of all non-first selects of a union to be compatible
+      by names with the columns of the first select. It will allow to use copies
+      of the same expression pushed into having clauses of different selects.
+    */
+    if (sl != first_sl)
+    {
+      DBUG_ASSERT(sl->item_list.elements == first_sl->item_list.elements);
+      List_iterator_fast<Item> it(sl->item_list);
+      List_iterator_fast<Item> nm_it(unit->types);
+      Item * item;
+      while((item= it++))
+      {
+        item->share_name_with(nm_it++);
+      }
+    }
+
     /*
       Transform the references to the 'derived' columns from the condition
       pushed into the having clause of sl to make them usable in the new context
diff --git a/sql/sql_insert.cc b/sql/sql_insert.cc
index 34c4211070b..b203fffaa72 100644
--- a/sql/sql_insert.cc
+++ b/sql/sql_insert.cc
@@ -3050,7 +3050,7 @@ pthread_handler_t handle_delayed_insert(void *arg)
     if (thd->mdl_context.clone_ticket(&di->grl_protection) ||
         thd->mdl_context.clone_ticket(&di->table_list.mdl_request))
     {
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       di->handler_thread_initialized= TRUE;
       goto err;
     }
@@ -3246,7 +3246,7 @@ pthread_handler_t handle_delayed_insert(void *arg)
     thd->set_killed(KILL_CONNECTION_HARD);	        // If error
 
     close_thread_tables(thd);			// Free the table
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
     mysql_cond_broadcast(&di->cond_client);       // Safety
 
     mysql_mutex_lock(&LOCK_delayed_create);    // Because of delayed_get_table
@@ -4722,7 +4722,8 @@ bool select_create::send_eof()
         WSREP_ERROR("Appending table key for CTAS failed: %s, %d",
                     (wsrep_thd_query(thd)) ?
                     wsrep_thd_query(thd) : "void", rcode);
-        return true;
+        abort_result_set();
+        DBUG_RETURN(true);
       }
       /* If commit fails, we should be able to reset the OK status. */
       thd->get_stmt_da()->set_overwrite_status(TRUE);
diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc
index 43bfa274537..c51a6f24aab 100644
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -2058,7 +2058,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
         locks.
       */
       trans_rollback_implicit(thd);
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
     }
 
     thd->cleanup_after_query();
@@ -2123,7 +2123,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     ulonglong options= (ulonglong) (uchar) packet[0];
     if (trans_commit_implicit(thd))
       break;
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
     if (check_global_access(thd,RELOAD_ACL))
       break;
     general_log_print(thd, command, NullS);
@@ -2156,7 +2156,7 @@ bool dispatch_command(enum enum_server_command command, THD *thd,
     if (trans_commit_implicit(thd))
       break;
     close_thread_tables(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
     my_ok(thd);
     break;
   }
@@ -2971,7 +2971,7 @@ err:
   /* Close tables and release metadata locks. */
   close_thread_tables(thd);
   DBUG_ASSERT(!thd->locked_tables_mode);
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
   return TRUE;
 }
 
@@ -3694,7 +3694,7 @@ mysql_execute_command(THD *thd)
       /* Commit the normal transaction if one is active. */
       bool commit_failed= trans_commit_implicit(thd);
       /* Release metadata locks acquired in this transaction. */
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       if (commit_failed)
       {
         WSREP_DEBUG("implicit commit failed, MDL released: %lld",
@@ -4938,7 +4938,7 @@ mysql_execute_command(THD *thd)
     {
       res= trans_commit_implicit(thd);
       thd->locked_tables_list.unlock_locked_tables(thd);
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       thd->variables.option_bits&= ~(OPTION_TABLE_LOCK);
     }
     if (thd->global_read_lock.is_acquired())
@@ -4952,7 +4952,7 @@ mysql_execute_command(THD *thd)
     res= trans_commit_implicit(thd);
     thd->locked_tables_list.unlock_locked_tables(thd);
     /* Release transactional metadata locks. */
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
     if (res)
       goto error;
 
@@ -5533,7 +5533,7 @@ mysql_execute_command(THD *thd)
     DBUG_PRINT("info", ("Executing SQLCOM_BEGIN  thd: %p", thd));
     if (trans_begin(thd, lex->start_transaction_opt))
     {
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       WSREP_DEBUG("BEGIN failed, MDL released: %lld",
                   (longlong) thd->thread_id);
       goto error;
@@ -5551,7 +5551,7 @@ mysql_execute_command(THD *thd)
                       (thd->variables.completion_type == 2 &&
                        lex->tx_release != TVL_NO));
     bool commit_failed= trans_commit(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
     if (commit_failed)
     {
       WSREP_DEBUG("COMMIT failed, MDL released: %lld",
@@ -5602,7 +5602,7 @@ mysql_execute_command(THD *thd)
                       (thd->variables.completion_type == 2 &&
                        lex->tx_release != TVL_NO));
     bool rollback_failed= trans_rollback(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
 
     if (rollback_failed)
     {
@@ -5915,7 +5915,6 @@ mysql_execute_command(THD *thd)
   case SQLCOM_XA_COMMIT:
   {
     bool commit_failed= trans_xa_commit(thd);
-    thd->mdl_context.release_transactional_locks();
     if (commit_failed)
     {
       WSREP_DEBUG("XA commit failed, MDL released: %lld",
@@ -5933,7 +5932,6 @@ mysql_execute_command(THD *thd)
   case SQLCOM_XA_ROLLBACK:
   {
     bool rollback_failed= trans_xa_rollback(thd);
-    thd->mdl_context.release_transactional_locks();
     if (rollback_failed)
     {
       WSREP_DEBUG("XA rollback failed, MDL released: %lld",
@@ -6161,7 +6159,7 @@ finish:
     */
     THD_STAGE_INFO(thd, stage_rollback_implicit);
     trans_rollback_implicit(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   }
   else if (stmt_causes_implicit_commit(thd, CF_IMPLICIT_COMMIT_END))
   {
@@ -6175,7 +6173,7 @@ finish:
       /* Commit the normal transaction if one is active. */
       trans_commit_implicit(thd);
       thd->get_stmt_da()->set_overwrite_status(false);
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
     }
   }
   else if (! thd->in_sub_stmt && ! thd->in_multi_stmt_transaction_mode())
@@ -6190,7 +6188,7 @@ finish:
       - If in autocommit mode, or outside a transactional context,
       automatically release metadata locks of the current statement.
     */
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   }
   else if (! thd->in_sub_stmt)
   {
@@ -6214,7 +6212,7 @@ finish:
   {
     WSREP_DEBUG("Forcing release of transactional locks for thd: %lld",
                 (longlong) thd->thread_id);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   }
 #endif /* WITH_WSREP */
 
diff --git a/sql/sql_prepare.cc b/sql/sql_prepare.cc
index 0c35b2dd1d8..b8c7eae638c 100644
--- a/sql/sql_prepare.cc
+++ b/sql/sql_prepare.cc
@@ -4247,7 +4247,7 @@ bool Prepared_statement::prepare(const char *packet, uint packet_len)
   if (thd->transaction_rollback_request)
   {
     trans_rollback_implicit(thd);
-    thd->mdl_context.release_transactional_locks();
+    thd->release_transactional_locks();
   }
 
   /* Preserve CHANGE MASTER attributes */
diff --git a/sql/sql_union.cc b/sql/sql_union.cc
index e73e55bd600..5fe9aea91ac 100644
--- a/sql/sql_union.cc
+++ b/sql/sql_union.cc
@@ -2059,6 +2059,7 @@ bool st_select_lex::cleanup()
     delete join;
     join= 0;
   }
+  leaf_tables.empty();
   for (SELECT_LEX_UNIT *lex_unit= first_inner_unit(); lex_unit ;
        lex_unit= lex_unit->next_unit())
   {
diff --git a/sql/sys_vars.cc b/sql/sys_vars.cc
index 60308e4413c..70c0a65ca5d 100644
--- a/sql/sys_vars.cc
+++ b/sql/sys_vars.cc
@@ -4037,7 +4037,7 @@ static bool fix_autocommit(sys_var *self, THD *thd, enum_var_type type)
     if (trans_commit_stmt(thd) || trans_commit(thd))
     {
       thd->variables.option_bits&= ~OPTION_AUTOCOMMIT;
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       WSREP_DEBUG("autocommit, MDL TRX lock released: %lld",
                   (longlong) thd->thread_id);
       return true;
diff --git a/sql/transaction.cc b/sql/transaction.cc
index e2c120ffebb..7f94d98179e 100644
--- a/sql/transaction.cc
+++ b/sql/transaction.cc
@@ -197,7 +197,7 @@ bool trans_begin(THD *thd, uint flags)
     Release transactional metadata locks only after the
     transaction has been committed.
   */
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
 
   // The RO/RW options are mutually exclusive.
   DBUG_ASSERT(!((flags & MYSQL_START_TRANS_OPT_READ_ONLY) &&
@@ -894,11 +894,13 @@ bool trans_xa_prepare(THD *thd)
 
 /**
   Commit and terminate the a XA transaction.
+  Transactional locks are released if transaction ended
 
   @param thd    Current thread
 
   @retval FALSE  Success
   @retval TRUE   Failure
+
 */
 
 bool trans_xa_commit(THD *thd)
@@ -989,6 +991,7 @@ bool trans_xa_commit(THD *thd)
   thd->transaction.xid_state.xa_state= XA_NOTR;
 
   trans_track_end_trx(thd);
+  thd->mdl_context.release_transactional_locks();
 
   DBUG_RETURN(res);
 }
@@ -996,6 +999,7 @@ bool trans_xa_commit(THD *thd)
 
 /**
   Roll back and terminate a XA transaction.
+  Transactional locks are released if transaction ended
 
   @param thd    Current thread
 
@@ -1046,6 +1050,7 @@ bool trans_xa_rollback(THD *thd)
   thd->transaction.xid_state.xa_state= XA_NOTR;
 
   trans_track_end_trx(thd);
+  thd->mdl_context.release_transactional_locks();
 
   DBUG_RETURN(res);
 }
diff --git a/sql/wsrep_applier.cc b/sql/wsrep_applier.cc
index 4e19e15680e..bc9b68400f4 100644
--- a/sql/wsrep_applier.cc
+++ b/sql/wsrep_applier.cc
@@ -189,7 +189,7 @@ static wsrep_cb_status_t wsrep_apply_events(THD*        thd,
       trans_rollback(thd);
       thd->locked_tables_list.unlock_locked_tables(thd);
       /* Release transactional metadata locks. */
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       thd->wsrep_conflict_state= NO_CONFLICT;
       DBUG_RETURN(WSREP_CB_FAILURE);
     }
@@ -371,7 +371,7 @@ wsrep_cb_status_t wsrep_commit_cb(void*         const     ctx,
 
   /* Cleanup */
   wsrep_set_apply_format(thd, NULL);
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
   thd->reset_query();                           /* Mutex protected */
   free_root(thd->mem_root,MYF(MY_KEEP_PREALLOC));
   thd->tx_isolation= (enum_tx_isolation) thd->variables.tx_isolation;
diff --git a/sql/wsrep_thd.cc b/sql/wsrep_thd.cc
index d00183abc80..d2c62e47edf 100644
--- a/sql/wsrep_thd.cc
+++ b/sql/wsrep_thd.cc
@@ -75,7 +75,7 @@ void wsrep_client_rollback(THD *thd)
   }
 
   /* Release transactional metadata locks. */
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
 
   /* release explicit MDL locks */
   thd->mdl_context.release_explicit_locks();
@@ -212,7 +212,7 @@ void wsrep_replay_sp_transaction(THD* thd)
     thd->locked_tables_list.unlock_locked_tables(thd);
     thd->variables.option_bits&= ~(OPTION_TABLE_LOCK);
   }
-  thd->mdl_context.release_transactional_locks();
+  thd->release_transactional_locks();
 
   mysql_mutex_unlock(&thd->LOCK_thd_data);
   THD *replay_thd= new THD(true);
@@ -351,7 +351,7 @@ void wsrep_replay_transaction(THD *thd)
         thd->locked_tables_list.unlock_locked_tables(thd);
         thd->variables.option_bits&= ~(OPTION_TABLE_LOCK);
       }
-      thd->mdl_context.release_transactional_locks();
+      thd->release_transactional_locks();
       /*
         Replaying will call MYSQL_START_STATEMENT when handling
         BEGIN Query_log_event so end statement must be called before