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set timestamp=unix_timestamp('2001-02-03 10:20:30');
create or replace table t1 (i int) with system versioning
partition by system_time interval 1 day
subpartition by key (i) subpartitions 2
(partition p1 history, partition pn current);
set timestamp=unix_timestamp('2001-02-03 10:20:40');
insert t1 values (1);
delete from t1;
set timestamp=unix_timestamp('2001-02-04 10:20:50');
insert t1 values (2);
Warnings:
Warning 4114 Versioned table `test`.`t1`: partition `p1` is full, add more HISTORY partitions
delete from t1;
Warnings:
Warning 4114 Versioned table `test`.`t1`: partition `p1` is full, add more HISTORY partitions
select subpartition_name,partition_description,table_rows from information_schema.partitions where table_schema='test' and table_name='t1';
subpartition_name partition_description table_rows
p1sp0 2001-02-04 10:20:30 1
p1sp1 2001-02-04 10:20:30 1
pnsp0 CURRENT 0
pnsp1 CURRENT 0
set timestamp=unix_timestamp('2001-02-04 10:20:55');
alter table t1 add partition (partition p0 history, partition p2 history);
set timestamp=unix_timestamp('2001-02-04 10:30:00');
insert t1 values (4),(5);
set timestamp=unix_timestamp('2001-02-04 10:30:10');
update t1 set i=6 where i=5;
select subpartition_name,partition_description,table_rows from information_schema.partitions where table_schema='test' and table_name='t1';
subpartition_name partition_description table_rows
p1sp0 2001-02-04 10:20:30 1
p1sp1 2001-02-04 10:20:30 0
p0sp0 2001-02-05 10:20:30 1
p0sp1 2001-02-05 10:20:30 1
p2sp0 2001-02-06 10:20:30 0
p2sp1 2001-02-06 10:20:30 0
pnsp0 CURRENT 0
pnsp1 CURRENT 2
## pruning check
set @ts=(select partition_description from information_schema.partitions
where table_schema='test' and table_name='t1' and partition_name='p0' limit 1);
select * from t1;
i
4
6
explain partitions select * from t1;
id select_type table partitions type possible_keys key key_len ref rows Extra
1 SIMPLE t1 pn_pnsp0,pn_pnsp1 ALL NULL NULL NULL NULL 2 Using where
explain partitions select * from t1 for system_time as of '2001-02-04 10:20:30';
id select_type table partitions type possible_keys key key_len ref rows Extra
1 SIMPLE t1 p1_p1sp0,p1_p1sp1,p0_p0sp0,p0_p0sp1,p2_p2sp0,p2_p2sp1,pn_pnsp0,pn_pnsp1 ALL NULL NULL NULL NULL # Using where
set @ts=(select row_end from t1 for system_time all where i=1);
select * from t1 for system_time all where row_end = @ts;
i
1
explain partitions select * from t1 for system_time all where row_end = @ts;
id select_type table partitions type possible_keys key key_len ref rows Extra
1 SIMPLE t1 p1_p1sp0,p1_p1sp1 # NULL NULL NULL NULL # #
drop table t1;
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