Fix for BUG#18025: Wrong query results because of bugs in partition pruning:

 - Fix typo bug in SEL_ARG::is_singlepoint()
 - In set_up_range_analysis_info(), treat MEDIUMINT as enumerable type just like other integer types


mysql-test/r/partition_pruning.result:
  Testcase for BUG#18025
mysql-test/t/partition_pruning.test:
  Testcase for BUG#18025
sql/opt_range.cc:
  BUG#18025: Fix a typo bug in SEL_ARG::is_singlepoint()
sql/sql_partition.cc:
  BUG#18025: In set_up_range_analysis_info(), treat MEDIUMINT as enumerable type just like other integer types.

1 files changed, 32 insertions, 0 deletions

diff --git a/mysql-test/t/partition_pruning.test b/mysql-test/t/partition_pruning.test
index 30f4f37ee04..25320e9f80d 100644
--- a/mysql-test/t/partition_pruning.test
+++ b/mysql-test/t/partition_pruning.test
@@ -447,5 +447,37 @@ show status like 'Handler_read_next';
 
 drop table t1, t2;
 
+# BUG#18025 
+#  part1: mediumint columns
+create table t1 ( f_int1 mediumint, f_int2 integer) 
+partition by list(mod(f_int1,4)) (
+  partition p_3 values in (-3),
+  partition p_2 values in (-2),
+  partition p_1 values in (-1),
+  partition p0 values in (0),
+  partition p1 values in (1),
+  partition p2 values in (2),
+  partition p3 values in (3)
+);
+
+insert into t1 values (9, 9), (8, 8), (7, 7), (6, 6), (5, 5), 
+                      (4, 4), (3, 3), (2, 2), (1, 1);
+select * from t1 where f_int1 between 5 and 15 order by f_int1;
+
+drop table t1;
+
+#  part2: bug in pruning code
+create table t1 (a char(10)) partition by list(length(a)) (
+  partition p1 values in (1),
+  partition p2 values in (2),
+  partition p3 values in (3),
+  partition p4 values in (4),
+  partition p5 values in (5)
+);
+insert into t1 values ('a'),('bb'),('ccc'),('dddd'),('eeEee');
+select * from t1 where a>='a' and a <= 'dddd';
+explain partitions select * from t1 where a>='a' and a <= 'dddd';
+drop table t1;
+
 # No tests for NULLs in RANGE(monotonic_expr()) - they depend on BUG#15447
 # being fixed.