Fix for LP BUG#714808 and LP BUG#719280.

The patch also adjusts several instable test results
to order the result.

Analysis:

The function prev_record_reads() may skip (jump over)
some query plan nodes where record_count < 1. At the
same time, even though get_partial_join_cost() uses
all first N plan nodes after the last constant table,
it may produce a smaller record_count than
prev_record_reads(), because the record count for
some plan nodes may be < 1, and these nodes may not
participate in prev_record_reads.

Solution:
The current solution is to treat the result of
get_partial_join_cost() as the upper bound for the
total number of unique lookup keys.

1 files changed, 20 insertions, 1 deletions

diff --git a/mysql-test/t/subselect_mat_cost.test b/mysql-test/t/subselect_mat_cost.test
index 0606cec80ed..3c5f1a680f9 100644
--- a/mysql-test/t/subselect_mat_cost.test
+++ b/mysql-test/t/subselect_mat_cost.test
@@ -366,7 +366,7 @@ EXPLAIN SELECT f2 FROM t3 WHERE (
         )
 ) IS NULL ;
 
-drop table t1, t2;
+drop table t1, t2, t3;
 
 --echo #
 --echo # LP BUG#715034 Item_sum_distinct::clear(): Assertion `tree != 0' failed
@@ -437,3 +437,22 @@ WHERE (SELECT t1.f1
 ORDER BY field1;
 
 drop table t1,t2;
+
+--echo #
+--echo # LP BUG#601124 Bug in eliminate_item_equal
+--echo # leads to crash in Item_func::Item_func
+
+CREATE TABLE t1 ( f1 int(11), f3 varchar(1)) ;
+INSERT INTO t1 VALUES (5,'m'),(NULL,'c');
+
+CREATE TABLE t2 ( f2 int(11), f3 varchar(1)) ;
+INSERT INTO t2 VALUES (6,'f'),(2,'d');
+
+CREATE TABLE t3 ( f2 int(11), f3 varchar(1)) ;
+INSERT INTO t3 VALUES (6,'f'),(2,'d');
+
+SELECT * FROM t3
+WHERE ( f2 ) IN (SELECT t1.f1
+                 FROM t1 STRAIGHT_JOIN t2 ON t2.f3 = t1.f3
+                 WHERE t2.f3 = 'c');
+drop table t1,t2,t3;