WL#2985 "Partition Pruning":

- post-...-post review fixes
- Added "integer range walking" that allows to do partition pruning for "a <=? t.field <=? b"
  by finding used partitions for a, a+1, a+2, ..., b-1, b. 


mysql-test/r/partition_pruning.result:
  WL#2985 "Partition Pruning": tests for "integer range walking"
mysql-test/t/partition.test:
  WL#2985 "Partition Pruning": post-review fixes
mysql-test/t/partition_pruning.test:
  WL#2985 "Partition Pruning": tests for "integer range walking"
sql/handler.h:
  WL#2985 "Partition Pruning": "integer range walking": 
  - class partition_info now has pointers to "partitioning interval analysis" functions
  - added "partition set iterator" definitions.
sql/opt_range.cc:
  WL#2985 "Partition Pruning": "integer range walking":
  - Switched to use "partitioning interval analysis" functions
  - Fixed two problems in find_used_partitions() that occur on complicated WHERE clauses.
sql/sql_partition.cc:
  WL#2985 "Partition Pruning": "integer range walking": 
  - Added "partitioning interval analysis" functions: get_part_iter_for_interval_via_mapping, 
    get_part_iter_for_interval_via_walking, 
  - Added appropriate partition-set-iterator implementations
  - Added a function to set up Partitioning Interval Analysis-related fields in partition_info.
sql/sql_select.cc:
  WL#2985 "Partition pruning": added comments.

1 files changed, 30 insertions, 0 deletions

diff --git a/mysql-test/r/partition_pruning.result b/mysql-test/r/partition_pruning.result
index ef431b2c00e..6f210a76778 100644
--- a/mysql-test/r/partition_pruning.result
+++ b/mysql-test/r/partition_pruning.result
@@ -274,3 +274,33 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	X	p1,p2	ALL	a	NULL	NULL	NULL	4	Using where
 1	SIMPLE	Y	p1,p2	ref	a	a	4	test.X.a	2	
 drop table t1;
+create table t1 (a int) partition by hash(a) partitions 20;
+insert into t1 values (1),(2),(3);
+explain partitions select * from t1 where a >  1 and a < 3;
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	p2	ALL	NULL	NULL	NULL	NULL	3	Using where
+explain partitions select * from t1 where a >= 1 and a < 3;
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	3	Using where
+explain partitions select * from t1 where a >  1 and a <= 3;
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	p2,p3	ALL	NULL	NULL	NULL	NULL	3	Using where
+explain partitions select * from t1 where a >= 1 and a <= 3;
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	p1,p2,p3	ALL	NULL	NULL	NULL	NULL	3	Using where
+drop table t1;
+create table t1 (a int, b int) 
+partition by list(a) subpartition by hash(b) subpartitions 20 
+(
+partition p0 values in (0),
+partition p1 values in (1),
+partition p2 values in (2),
+partition p3 values in (3)
+);
+insert into t1 values (1,1),(2,2),(3,3);
+explain partitions select * from t1 where b >  1 and b < 3;
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	p0_sp2,p1_sp2,p2_sp2,p3_sp2	ALL	NULL	NULL	NULL	NULL	3	Using where
+explain partitions select * from t1 where b >  1 and b < 3 and (a =1 or a =2);
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	p1_sp2,p2_sp2	ALL	NULL	NULL	NULL	NULL	3	Using where