Vertica删除历史分区数据

假设test用户下创建的t_jingyu表

vsql -Utest -wtestpwd

create table t_jingyu(

col1 int,

col2 varchar,

col3 timestamp not null)

PARTITION BY (date_part('doy', t_jingyu.col3));

 

需求：删除doy分区表t_jingyu的历史分区数据(8月份)

$vi /tmp/jingyu/del_part08_01-.sql

\timing
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-01'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-02'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-03'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-04'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-05'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-06'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-07'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-08'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-09'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-10'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-11'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-12'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-13'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-14'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-15'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-16'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-17'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-18'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-19'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-20'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-21'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-22'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-23'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-24'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-25'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-26'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-27'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-28'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-29'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-30'::date));
SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-31'::date)); 

$vsql -Utest -wtestpwd -f /tmp/jingyu/del_part08_01-.sql

Timing is on.
  DROP_PARTITION
-------------------
 Partition dropped
(1 row)

Time: First fetch (1 row): 12732.105 ms. All rows formatted: 12732.215 ms
  DROP_PARTITION
-------------------
 Partition dropped
(1 row)

Time: First fetch (1 row): 71796.168 ms. All rows formatted: 71796.237 ms
……
Time: First fetch (1 row): 16020.296 ms. All rows formatted: 16020.362 ms
[dbadmin@Vertica01 jingyu]$ 

数据库表有入库时，drop历史分区会有锁等待，如下：

dbadmin=> SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-04'::date));
 ERROR 5157:  Unavailable: [Txn 0xa000000005fb08] O lock table - timeout error Timed out O locking Table:test.t_jingyu. I held by [user dbadmin (copy test.t_jingyu(col1,col2,col3)
from '/home/dbadmin/bin/vertica97/data/t_jingyudat1411006284757/*' on any node
delimiter E'~' NULL '' NO ESCAPE DIRECT;)], I held by [user dbadmin (copy test.t_jingyu(col1,col2,col3)
from '/home/dbadmin/bin/vertica101/data/t_jingyudat1411006351418/*' on any node
delimiter E'~' NULL '' NO ESCAPE DIRECT;)]. Your current transaction isolation level is SERIALIZABLE
dbadmin=>
同时关注数据库的队列，发现同时有drop_partition和copy入库。
dbadmin=> select substr(current_statement, 1, 200), count(1)
dbadmin-> from sessions
dbadmin-> where not current_statement is null and (transaction_id, statement_id)<>(current_trans_id(), current_statement())
dbadmin-> group by 1;
                                                                                                  substr                                                                                                  | count
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-------
                                                                                                                                                                                                          |    10
 SELECT DROP_PARTITION('test.t_jingyu', EXTRACT('doy' FROM '2014-08-04'::date));                                                                                                                |     1
 copy test.t_jingyu(col1,col2,col3) f |     1
(3 rows)

在没有copy入库时，drop_partition 大概20s内就可以删除一个历史分区（50亿左右数据量）。