From: Date: May 15 2007 10:30pm
Subject: bk commit into 5.0 tree (evgen:1.2487) BUG#28208
List-Archive: http://lists.mysql.com/commits/26737
X-Bug: 28208
Message-Id: <20070515203015.5C7F022CB9F@moonbone.moonbone.local>

Below is the list of changes that have just been committed into a local
5.0 repository of evgen. When evgen 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@stripped, 2007-05-16 00:30:12+04:00, evgen@stripped +3 -0
  Bug#28208: Wrong result of a non-const STRING function with a const DATETIME
  function.
  
  A wrong  condition was used to check that the
  Arg_comparator::can_compare_as_dates() function calculated the value of the
  string constant. When comparing a non-const STRING function with a constant
  DATETIME function it leads to saving an arbitrary value as a cached value of
  the DATETIME function.
  
  Now the Arg_comparator::set_cmp_func() function initializes the const_value
  variable to the impossible DATETIME value (-1) and this const_value is
  cached only if it was changed by the Arg_comparator::can_compare_as_dates()
  function.

  mysql-test/r/type_datetime.result@stripped, 2007-05-16 00:29:50+04:00, evgen@stripped +6 -0
    Added a test case for the bug#28208: Wrong result of a non-const STRING function with a const DATETIME function.

  mysql-test/t/type_datetime.test@stripped, 2007-05-16 00:29:48+04:00, evgen@stripped +9 -0
    Added a test case for the bug#28208: Wrong result of a non-const STRING function with a const DATETIME function.

  sql/item_cmpfunc.cc@stripped, 2007-05-16 00:29:50+04:00, evgen@stripped +2 -3
    Bug#28208: Wrong result of a non-const STRING function with a const DATETIME
    function.
    Now the Arg_comparator::set_cmp_func() function initializes the const_value
    variable to the impossible DATETIME value (-1) and this const_value is
    cached only if it was changed by the Arg_comparator::can_compare_as_dates()
    function.

# 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:	evgen
# Host:	moonbone.local
# Root:	/mnt/gentoo64/work/28208-bug-5.0-opt-mysql

--- 1.250/sql/item_cmpfunc.cc	2007-05-07 22:22:16.000000000 +0400
+++ 1.251/sql/item_cmpfunc.cc	2007-05-16 00:29:50.000000000 +0400
@@ -661,7 +661,7 @@
                                         Item_result type)
 {
   enum enum_date_cmp_type cmp_type;
-  ulonglong const_value;
+  ulonglong const_value= (ulonglong)-1;
   a= a1;
   b= a2;
 
@@ -674,8 +674,7 @@
     a_cache= 0;
     b_cache= 0;
 
-    if (cmp_type != CMP_DATE_WITH_DATE &&
-        ((*b)->const_item() || (*a)->const_item()))
+    if (const_value != (ulonglong)-1)
     {
       Item_cache_int *cache= new Item_cache_int();
       /* Mark the cache as non-const to prevent re-caching. */

--- 1.42/mysql-test/r/type_datetime.result	2007-05-11 19:56:20.000000000 +0400
+++ 1.43/mysql-test/r/type_datetime.result	2007-05-16 00:29:50.000000000 +0400
@@ -346,3 +346,9 @@
 a	b	a_then_b	b_then_a	c_then_a
 2007-04-10	2007-04-11	2007-04-10	2007-04-10	2004-04-09 00:00:00
 drop procedure test27759;
+create table t1 (f1 date);
+insert into t1 values (curdate());
+select left(f1,10) = curdate() from t1;
+left(f1,10) = curdate()
+1
+drop table t1;

--- 1.28/mysql-test/t/type_datetime.test	2007-05-11 19:56:20.000000000 +0400
+++ 1.29/mysql-test/t/type_datetime.test	2007-05-16 00:29:48.000000000 +0400
@@ -225,3 +225,12 @@
 DELIMITER ;|
 call test27759();
 drop procedure test27759;
+
+#
+# Bug#28208: Wrong result of a non-const STRING function with a const
+#            DATETIME function.
+#
+create table t1 (f1 date);
+insert into t1 values (curdate());
+select left(f1,10) = curdate() from t1;
+drop table t1;