Commit a4a1bb0e authored by unknown's avatar unknown
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WL#2985 "Partition Pruning": post-review fixes: 

- Added more comments.
- Added a RANGE_OPT_PARAM::remove_jump_scans flag that disables construction of index_merge
  SEL_TREEs that represent unusable conditions like "key1part1<c1 OR key2part2<c2"
- make prune_partitions() function handle the case where range analysis produces a list of 
  index_merge trees (it turned out that this is possible, appropriate test case added).
- Other small fixes.


mysql-test/r/partition_pruning.result:
  WL#2985 "Partition Pruning": post-review fixes: more test cases
mysql-test/t/partition_pruning.test:
  WL#2985 "Partition Pruning": post-review fixes: more test cases
sql/opt_range.cc:
  WL#2985 "Partition Pruning": post-review fixes:
  - Added more comments.
  - Fix the debug printouts
  - Added a RANGE_OPT_PARAM::remove_jump_scans flag that disables construction of index_merge
    SEL_TREEs that represent unusable conditions like "key1part1<c1 OR key2part2<c2"
  - make prune_partitions() function handle the case where range analysis produces a list of 
    index_merge trees (it turned out that this is possible, appropriate test case added).
sql/sql_partition.cc:
  WL#2985 "Partition Pruning": post-review fixes: make requested edits in comments.
sql/table.h:
  WL#2985 "Partition Pruning": post-review fixes: added bool TABLE::no_partitions_used
  (this change was missed when making the original cset)
parent f19fb870

mysql-test/r/partition_pruning.result

+45 −0
Original line number Diff line number Diff line
@@ -213,3 +213,48 @@ explain partitions select * from t1 where a='b'; 
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	3	Using where

drop table t1;

create table t1 (

a1 int not null

)

partition by range (a1) (

partition p0 values less than (3),

partition p1 values less than (6),

partition p2 values less than (9)

);

insert into t1 values (1),(2),(3);

explain partitions select * from t1 where a1 > 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 a1 >= 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 a1 < 3 and a1 > 3;

id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables

drop table t1;

create table t3 (a int, b int) 

partition by list(a) subpartition by hash(b) subpartitions 4 (

partition p0 values in (1),

partition p1 values in (2),

partition p2 values in (3),

partition p3 values in (4)

);

insert into t3 values (1,1),(2,2),(3,3);

explain partitions select * from t3 where a=2 or b=1;

id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t3	p0_sp1,p1_sp0,p1_sp1,p1_sp2,p1_sp3,p2_sp1,p3_sp1	ALL	NULL	NULL	NULL	NULL	3	Using where

explain partitions select * from t3 where a=4 or b=2;

id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t3	p0_sp2,p1_sp2,p2_sp2,p3_sp0,p3_sp1,p3_sp2,p3_sp3	ALL	NULL	NULL	NULL	NULL	3	Using where

explain partitions select * from t3 where (a=2 or b=1) and (a=4 or b=2) ;

id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t3	p1_sp2,p3_sp1	ALL	NULL	NULL	NULL	NULL	3	Using where

create table t1 (a int) partition by hash(a) partitions 2;

insert into t1 values (1),(2);

explain partitions select * from t1 where a is null;

id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	2	Using where

explain partitions select * from t1 where a is not null;

id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	2	Using where

drop table t1;

mysql-test/t/partition_pruning.test

+42 −0
Original line number Diff line number Diff line
@@ -192,4 +192,46 @@ insert into t1 values ('a'),('b'),('c'); 
explain partitions select * from t1 where a='b';

drop table t1;



#

# Test cases for bugs found in code review:

#

create table t1 (

  a1 int not null

)

partition by range (a1) (

  partition p0 values less than (3),

  partition p1 values less than (6),

  partition p2 values less than (9)

);

insert into t1 values (1),(2),(3);

explain partitions select * from t1 where a1 > 3;

explain partitions select * from t1 where a1 >= 3;



explain partitions select * from t1 where a1 < 3 and a1 > 3;

drop table t1;



#

create table t3 (a int, b int) 

  partition by list(a) subpartition by hash(b) subpartitions 4 (

    partition p0 values in (1),

    partition p1 values in (2),

    partition p2 values in (3),

    partition p3 values in (4)

  );

insert into t3 values (1,1),(2,2),(3,3);



explain partitions select * from t3 where a=2 or b=1;

explain partitions select * from t3 where a=4 or b=2;

explain partitions select * from t3 where (a=2 or b=1) and (a=4 or b=2) ;



# Test for NULLs

create table t1 (a int) partition by hash(a) partitions 2;

insert into t1 values (1),(2);

explain partitions select * from t1 where a is null;



# this selects both

explain partitions select * from t1 where a is not null;

drop table t1;



# No tests for NULLs in RANGE(monotonic_expr()) - they depend on BUG#15447

# being fixed.

sql/opt_range.cc

+371 −53

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sql/sql_partition.cc

+17 −16

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sql/table.h

+1 −0
Original line number Diff line number Diff line
@@ -297,6 +297,7 @@ struct st_table { 
  FILESORT_INFO sort;

#ifdef WITH_PARTITION_STORAGE_ENGINE

  partition_info *part_info;            /* Partition related information */

  bool no_partitions_used; /* If true, all partitions have been pruned away */

#endif



  bool fill_item_list(List<Item> *item_list) const;