At file:///home/psergey/dev/maria-5.3-subqueries-r10/
------------------------------------------------------------
revno: 2782
revision-id: psergey@askmonty.org-20100320165930-ehfull9rin1bdme4
parent: psergey@askmonty.org-20100320120844-n8dvu5loib2fjvwl
committer: Sergey Petrunya
branch nick: maria-5.3-subqueries-r10
timestamp: Sat 2010-03-20 19:59:30 +0300
message:
Fix union.test failure in buildbot: alternate fix for BUG#49734
=== modified file 'mysql-test/r/union.result'
--- a/mysql-test/r/union.result 2010-03-20 12:01:47 +0000
+++ b/mysql-test/r/union.result 2010-03-20 16:59:30 +0000
@@ -1632,7 +1632,7 @@
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 100.00
2 UNION t1 ALL NULL NULL NULL NULL 2 100.00
-3 SUBQUERY t2 ALL NULL NULL NULL NULL 2 100.00 Using where
+3 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 2 100.00 Using where
NULL UNION RESULT ALL NULL NULL NULL NULL NULL NULL Using filesort
Warnings:
Note 1276 Field or reference 'test.t1.a' of SELECT #3 was resolved in SELECT #2
=== modified file 'sql/sql_select.cc'
--- a/sql/sql_select.cc 2010-03-20 12:01:47 +0000
+++ b/sql/sql_select.cc 2010-03-20 16:59:30 +0000
@@ -18319,6 +18319,26 @@
unit;
unit= unit->next_unit())
{
+ /*
+ This fix_fields() call is to handle an edge case like this:
+
+ SELECT ... UNION SELECT ... ORDER BY (SELECT ...)
+
+ for such queries, we'll get here before having called
+ subquery_expr->fix_fields(), which will cause failure to
+ */
+ if (unit->item && !unit->item->fixed)
+ {
+ Item *ref= unit->item;
+ if (unit->item->fix_fields(thd, &ref))
+ DBUG_VOID_RETURN;
+ DBUG_ASSERT(ref == unit->item);
+ }
+
+ /*
+ Display subqueries only if they are not parts of eliminated WHERE/ON
+ clauses.
+ */
if (!(unit->item && unit->item->eliminated))
{
if (mysql_explain_union(thd, unit, result))
Sergey Petrunya