bk commit into 4.0 tree (ramil:1.2086) BUG#8942

[ramil]

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

ChangeSet
  1.2086 05/03/17 10:24:50 ramil@stripped +3 -0
  A fix (bug #8942: SUBSTRING_INDEX in UPDATE causes internal loop).

  sql/key.cc
    1.19 05/03/17 10:24:48 ramil@stripped +1 -1
    A fix (bug #8942: SUBSTRING_INDEX in UPDATE causes internal loop).
    For "partial" key parts (e.g. key(a(20), ...) we create different
    key_part->field, see sql/table.cc; so we have to use the eq() 
    function here to compare fields.

  mysql-test/t/update.test
    1.15 05/03/17 10:24:48 ramil@stripped +10 -0
    A fix (bug #8942: SUBSTRING_INDEX in UPDATE causes internal loop).

  mysql-test/r/update.result
    1.17 05/03/17 10:24:48 ramil@stripped +7 -0
    A fix (bug #8942: SUBSTRING_INDEX in UPDATE causes internal loop).

# 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:	ramil
# Host:	gw.mysql.r18.ru
# Root:	/usr/home/ram/work/4.0.b8942

--- 1.18/sql/key.cc	2004-01-20 02:44:37 +04:00
+++ 1.19/sql/key.cc	2005-03-17 10:24:48 +04:00
@@ -265,7 +265,7 @@
     f.rewind();
     while ((field=(Item_field*) f++))
     {
-      if (key_part->field == field->field)
+      if (key_part->field->eq(field->field))
 	return 1;
     }
   }

--- 1.16/mysql-test/r/update.result	2004-12-18 15:57:13 +04:00
+++ 1.17/mysql-test/r/update.result	2005-03-17 10:24:48 +04:00
@@ -209,3 +209,10 @@
 update t1 left join t2 on t1.c1 = t2.c1 set t2.c2 = "t2c2-1";
 update t1 left join t2 on t1.c1 = t2.c1 set t2.c2 = "t2c2-1" where t1.c3 = 10;
 drop table t1, t2;
+create table t1 (a int, b char(255), key(a, b(20)));
+insert into t1 values (0, '1');
+update t1 set b = b + 1 where a = 0;
+select * from t1;
+a	b
+0	2
+drop table t1;

--- 1.14/mysql-test/t/update.test	2004-12-16 20:44:37 +04:00
+++ 1.15/mysql-test/t/update.test	2005-03-17 10:24:48 +04:00
@@ -164,3 +164,13 @@
 update t1 left join t2 on t1.c1 = t2.c1 set t2.c2 = "t2c2-1";
 update t1 left join t2 on t1.c1 = t2.c1 set t2.c2 = "t2c2-1" where t1.c3 = 10;
 drop table t1, t2;
+
+#
+# Bug #8942: a problem with update and partial key part
+#
+
+create table t1 (a int, b char(255), key(a, b(20)));
+insert into t1 values (0, '1');
+update t1 set b = b + 1 where a = 0;
+select * from t1;
+drop table t1;