From: Date: June 5 2005 7:48pm
Subject: bk commit into 5.0 tree (konstantin:1.1913) BUG#7306
List-Archive: http://lists.mysql.com/internals/25619
X-Bug: 7306
Message-Id: <20050605174823.EFCB1A97A@dragonfly.local>

Below is the list of changes that have just been committed into a local
5.0 repository of kostja. When kostja does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
For information on how to access the public repository
see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet
  1.1913 05/06/05 21:48:16 konstantin@stripped +1 -0
  á followup patch for the patch for bug#7306: in case we're in
  statement prepare, prevent evaluation of subselects, even if they're
  not correlated.

  sql/item_subselect.cc
    1.108 05/06/05 21:48:10 konstantin@stripped +8 -5
    á followup patch for the patch for bug#7306: in case we're in
    statement prepare, prevent evaluation of subselects, even if they're
    not correlated.

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	konstantin
# Host:	dragonfly.local
# Root:	/opt/local/work/mysql-5.0-7306-final

--- 1.107/sql/item_subselect.cc	2005-06-04 16:33:49 +04:00
+++ 1.108/sql/item_subselect.cc	2005-06-05 21:48:10 +04:00
@@ -182,12 +182,15 @@
   else
     return 1;
   uint8 uncacheable= engine->uncacheable();
-  if (uncacheable)
-  {
+  /*
+    Mark this item as non-const unless this subselect is not correlated.
+    Also temporarily switch off const if we're in prepare (to avoid
+    unneeded query evaluation at prepare).
+  */
+  if (uncacheable || thd->current_arena->is_stmt_prepare())
     const_item_cache= 0;
-    if (uncacheable & UNCACHEABLE_RAND)
-      used_tables_cache|= RAND_TABLE_BIT;
-  }
+  if (uncacheable & UNCACHEABLE_RAND)
+    used_tables_cache|= RAND_TABLE_BIT;
   fixed= 1;
   thd->where= save_where;
   return res;