Information that Can Be Pruned

Partition pruning can be performed on partitioned columns.

MogDB prunes partitions when you use range, LIKE, equality, and IN list predicates on range or list partition columns, and equality and IN list predicates on hash partition columns.

In example 1, table prune_tt01 is partitioned by range on column A.

MogDB uses predicates on partition columns to perform partition pruning, as shown below.

Example 1 Createing a table with partition pruning

CREATE TABLE prune_tt01(a int, b int)
PARTITION BY RANGE(a)
(
  PARTITION prune_tt01_p1 VALUES LESS THAN(5),
  PARTITION prune_tt01_p2 VALUES LESS THAN(10),
  PARTITION prune_tt01_p3 VALUES LESS THAN(15),
  PARTITION prune_tt01_p4 VALUES LESS THAN(MAXVALUE)
);
INSERT INTO prune_tt01 VALUES (generate_series(1, 20), generate_series(1,20));
CREATE INDEX index_prune_tt01 ON prune_tt01 USING btree(a) LOCAL;

select * from prune_tt01 where a > 8 ;