From c864ac15a57d2f9f39fca646dab844b1ad0c1477 Mon Sep 17 00:00:00 2001
From: "ingo@mysql.com" <>
Date: Wed, 5 Apr 2006 14:39:20 +0200
Subject: [PATCH] BUG#5390 - problems with merge tables Additional fix for
 INSERT DELAYED with subselect. Originally detected in 5.1, but 5.0 could also
 be affected. The user thread creates a dummy table object, which is not
 included in the lock. The 'real' table is opened and locked by the 'delayed'
 system thread. The dummy object is now marked as not locked and this is
 tested in mysql_lock_have_duplicate().

---
 sql/lock.cc       | 13 +++++++++----
 sql/sql_insert.cc |  5 ++++-
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/sql/lock.cc b/sql/lock.cc
index 01cdca0b6ee..a584b063a0b 100644
--- a/sql/lock.cc
+++ b/sql/lock.cc
@@ -530,8 +530,11 @@ TABLE_LIST *mysql_lock_have_duplicate(THD *thd, TABLE_LIST *needle,
   THR_LOCK_DATA         **end_data2;
   DBUG_ENTER("mysql_lock_have_duplicate");
 
-  /* Table may not be defined for derived or view tables. */
-  if (! (table= needle->table))
+  /*
+    Table may not be defined for derived or view tables.
+    Table may not be part of a lock for delayed operations.
+  */
+  if (! (table= needle->table) || ! table->lock_count)
     goto end;
 
   /* A temporary table does not have locks. */
@@ -550,7 +553,8 @@ TABLE_LIST *mysql_lock_have_duplicate(THD *thd, TABLE_LIST *needle,
   lock_tables= mylock->table;
 
   /* Prepare table related variables that don't change in loop. */
-  DBUG_ASSERT(table == lock_tables[table->lock_position]);
+  DBUG_ASSERT((table->lock_position < mylock->table_count) &&
+              (table == lock_tables[table->lock_position]));
   table_lock_data= lock_locks + table->lock_data_start;
   end_data= table_lock_data + table->lock_count;
 
@@ -563,7 +567,8 @@ TABLE_LIST *mysql_lock_have_duplicate(THD *thd, TABLE_LIST *needle,
       continue;
 
     /* All tables in list must be in lock. */
-    DBUG_ASSERT(table2 == lock_tables[table2->lock_position]);
+    DBUG_ASSERT((table2->lock_position < mylock->table_count) &&
+                (table2 == lock_tables[table2->lock_position]));
 
     for (lock_data2=  lock_locks + table2->lock_data_start,
            end_data2= lock_data2 + table2->lock_count;
diff --git a/sql/sql_insert.cc b/sql/sql_insert.cc
index ad9606acb83..67aab57b880 100644
--- a/sql/sql_insert.cc
+++ b/sql/sql_insert.cc
@@ -1536,7 +1536,10 @@ TABLE *delayed_insert::get_local_table(THD* client_thd)
 
   /* Adjust in_use for pointing to client thread */
   copy->in_use= client_thd;
-  
+
+  /* Adjust lock_count. This table object is not part of a lock. */
+  copy->lock_count= 0;
+
   return copy;
 
   /* Got fatal error */