Minor fixes of the patch for BUG#6303

mysql-test/r/group_min_max.result:
  Test results for BUG#6303
mysql-test/t/group_min_max.test:
  Ucommented tests for BUG#6303
sql/opt_range.cc:
  Comment fix

mysql-test/r/group_min_max.result

@@ -1354,6 +1354,18 @@ c	a	a	b311	d311
 c	a	b	e312	h312
 d	a	a	b411	d411
 d	a	b	e412	h412
+explain select a1,a2,b,min(c),max(c) from t1
+where exists ( select * from t2 where t2.c = t1.c )
+group by a1,a2,b;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	index	NULL	idx_t1_1	163	NULL	128	Using where; Using index
+2	DEPENDENT SUBQUERY	t2	index	NULL	idx_t2_1	163	NULL	164	Using where; Using index
+explain select a1,a2,b,min(c),max(c) from t1
+where exists ( select * from t2 where t2.c > 'b1' )
+group by a1,a2,b;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	range	NULL	idx_t1_1	147	NULL	17	Using index for group-by
+2	SUBQUERY	t2	index	NULL	idx_t2_1	163	NULL	164	Using index
 explain select a1,a2,b,min(c),max(c) from t1 where (a1 >= 'c' or a2 < 'b') and (b > 'a') group by a1,a2,b;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	range	idx_t1_0,idx_t1_1,idx_t1_2	idx_t1_1	147	NULL	17	Using where; Using index for group-by
@@ -1637,6 +1649,14 @@ a1	a2	b
 select distinct b from t2 where (a2 >= 'b') and (b = 'a');
 b
 a
+select distinct t_00.a1
+from t1 t_00
+where exists ( select * from t2 where a1 = t_00.a1 );
+a1
+a
+b
+c
+d
 explain select distinct a1,a2,b from t1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	range	NULL	idx_t1_1	147	NULL	17	Using index for group-by

mysql-test/t/group_min_max.test

@@ -372,15 +372,15 @@ select a1,a2,b,min(c),max(c) from t2 where (c > 'b111') and (c <= 'g112') group
 select a1,a2,b,min(c),max(c) from t2 where (c < 'c5') or (c = 'g412') or (c = 'k421') group by a1,a2,b;
 select a1,a2,b,min(c),max(c) from t2 where ((c > 'b111') and (c <= 'g112')) or ((c > 'd000') and (c <= 'i110')) group by a1,a2,b;
 
-#-- analyze the sub-select
-#explain select a1,a2,b,min(c),max(c) from t1
-#where exists ( select * from t2 where t2.c = t1.c )
-#group by a1,a2,b;
+-- analyze the sub-select
+explain select a1,a2,b,min(c),max(c) from t1
+where exists ( select * from t2 where t2.c = t1.c )
+group by a1,a2,b;
 
-#-- the sub-select is unrelated to MIN/MAX
-#explain select a1,a2,b,min(c),max(c) from t1
-#where exists ( select * from t2 where t2.c > 'b1' )
-#group by a1,a2,b;
+-- the sub-select is unrelated to MIN/MAX
+explain select a1,a2,b,min(c),max(c) from t1
+where exists ( select * from t2 where t2.c > 'b1' )
+group by a1,a2,b;
 
 
 -- A,B,C) Predicates referencing mixed classes of attributes
@@ -474,10 +474,10 @@ select distinct a1,a2,b,c from t2 where (a2 >= 'b') and (b = 'a') and (c = 'i121
 select distinct a1,a2,b from t2 where (a1 > 'a') and (a2 > 'a') and (b = 'c');
 select distinct b from t2 where (a2 >= 'b') and (b = 'a');
 
-#-- BUG 6303
-#select distinct t_00.a1
-#from t1 t_00
-#where exists ( select * from t2 where a1 = t_00.a1 );
+-- BUG 6303
+select distinct t_00.a1
+from t1 t_00
+where exists ( select * from t2 where a1 = t_00.a1 );
 
 
 --

sql/opt_range.cc

@@ -6965,8 +6965,9 @@ check_group_min_max_predicates(COND *cond, Item_field *min_max_arg_item,
     if (cur_arg->type() == Item::FIELD_ITEM)
     {
       if (min_max_arg_item->eq(cur_arg, 1)) 
-      {/*
-         If pred references the MIN/MAX argument check whether pred is a range
+      {
+       /*
+         If pred references the MIN/MAX argument, check whether pred is a range
          condition that compares the MIN/MAX argument with a constant.
        */
         Item_func::Functype pred_type= pred->functype();