From: Davi Arnaut
Date: March 23 2009 6:17pm
Subject: bzr commit into mysql-6.0 branch (davi:2746) Bug#989 WL#4284
List-Archive: http://lists.mysql.com/commits/70102
X-Bug: 989
Message-Id: <20090323181717.09252EC178@skynet.ctb.virtua.com.br>
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="===============9092592831645036171=="

--===============9092592831645036171==
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

# At a local mysql-6.0 repository of davi

 2746 Davi Arnaut	2009-03-23
      Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order
      WL#4284: Transactional DDL locking
      
      After some discussions with stakeholders it has been decided that
      metadata locks acquired during a PREPARE statement must be released
      once the statement is prepared even if it is prepared within a multi
      statement transaction.
     @ mysql-test/r/ps.result
        Add test case result.
     @ mysql-test/t/ps.test
        Add test case.
     @ sql/sql_prepare.cc
        Release metdata locks acquired while the prepared statement is being
        checked.

    modified:
      mysql-test/r/ps.result
      mysql-test/t/ps.test
      sql/sql_prepare.cc
=== modified file 'mysql-test/r/ps.result'
--- a/mysql-test/r/ps.result	2009-03-18 12:49:07 +0000
+++ b/mysql-test/r/ps.result	2009-03-23 18:17:10 +0000
@@ -3096,6 +3096,16 @@ EXECUTE stmt1;
 ERROR 42S01: Table 't1' already exists
 DEALLOCATE PREPARE stmt1;
 DROP TABLE t1;
+#
+# WL#4284: Transactional DDL locking
+#
+# Test that metadata locks taken during prepare are released.
+#
+DROP TABLE IF EXISTS t1;
+CREATE TABLE t1 (a INT);
+BEGIN;
+PREPARE stmt1 FROM "SELECT * FROM t1";
+DROP TABLE t1;
 
 # End of WL#4435.
 

=== modified file 'mysql-test/t/ps.test'
--- a/mysql-test/t/ps.test	2009-03-18 12:49:07 +0000
+++ b/mysql-test/t/ps.test	2009-03-23 18:17:10 +0000
@@ -3212,6 +3212,25 @@ EXECUTE stmt1;
 DEALLOCATE PREPARE stmt1;
 DROP TABLE t1;
 
+--echo #
+--echo # WL#4284: Transactional DDL locking
+--echo #
+--echo # Test that metadata locks taken during prepare are released.
+--echo #
+
+connect(con1,localhost,root,,);
+connection default;
+--disable_warnings
+DROP TABLE IF EXISTS t1;
+--enable_warnings
+CREATE TABLE t1 (a INT);
+connection con1;
+BEGIN;
+PREPARE stmt1 FROM "SELECT * FROM t1";
+connection default;
+DROP TABLE t1;
+disconnect con1;
+
 #
 # Additional cleanup.
 #

=== modified file 'sql/sql_prepare.cc'
--- a/sql/sql_prepare.cc	2009-03-18 12:49:07 +0000
+++ b/sql/sql_prepare.cc	2009-03-23 18:17:10 +0000
@@ -3147,6 +3147,7 @@ bool Prepared_statement::prepare(const c
   bool error;
   Statement stmt_backup;
   Query_arena *old_stmt_arena;
+  MDL_ticket *mdl_savepoint= NULL;
   DBUG_ENTER("Prepared_statement::prepare");
   /*
     If this is an SQLCOM_PREPARE, we also increase Com_prepare_sql.
@@ -3205,6 +3206,13 @@ bool Prepared_statement::prepare(const c
   */
   DBUG_ASSERT(thd->change_list.is_empty());
 
+  /*
+    Marker used to release metadata locks acquired while the prepared
+    statement is being checked.
+  */
+  if (thd->in_multi_stmt_transaction())
+    mdl_savepoint= thd->mdl_context.mdl_savepoint();
+
   /* 
    The only case where we should have items in the thd->free_list is
    after stmt->set_params_from_vars(), which may in some cases create
@@ -3228,6 +3236,15 @@ bool Prepared_statement::prepare(const c
 
   lex_end(lex);
   cleanup_stmt();
+  /*
+    If not inside a multi-statement transaction, the metadata locks have
+    already been released and the rollback_to_savepoint is a nop.
+    Otherwise, release acquired locks -- a NULL mdl_savepoint means that
+    all locks are going to be released or that the transaction didn't
+    own any locks.
+  */
+  if (!thd->locked_tables_mode)
+    thd->mdl_context.rollback_to_savepoint(mdl_savepoint);
   thd->restore_backup_statement(this, &stmt_backup);
   thd->stmt_arena= old_stmt_arena;
 


--===============9092592831645036171==
MIME-Version: 1.0
Content-Type: text/bzr-bundle; charset="us-ascii";
	name="bzr/davi.arnaut@stripped"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

# Bazaar merge directive format 2 (Bazaar 0.90)
# revision_id: davi.arnaut@stripped
# target_branch: file:///home/davi/bzr/stage/mysql-6.0-runtime/
# testament_sha1: af051fa3437fb0f17285aa2d3ef789cf8b6e437a
# timestamp: 2009-03-23 15:17:16 -0300
# base_revision_id: davi.arnaut@stripped\
#   28o62nkdatwf78c5
# 
# Begin bundle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--===============9092592831645036171==--