【发布时间】:2014-01-03 14:35:51
【问题描述】:
我有一个执行超过 10 秒的查询。请提供一些建议来即兴以下查询!
CREATE TABLE uem_map_user_event (
id INT(11) , uem_user_id INt(10),uem_event_type_id INT(11),
uem_entry_date DATETIME ,INDEX urt_user_id (uem_user_id) );
CREATE TABLE evy_mst_event_type (id INT(11) , evy_description VARCHAR(45),
evy_event_family_id INT(11),PRIMARY KEY (id) );
CREATE TABLE uft_map_user_clnt (
id INT(11) ,uft_user_id INT(11) ,uft_clnt_id INT(11) ,uft_eff_frmdt DATETIME ,
uft_eff_todt DATETIME ,uft_add_userid INT(11) ,uft_mod_userid INT(11) );
select * from (
select u.id as id,evy.description as 'Work Description',count(*) as Pending
from user_event u
join event_type evy on evy.id = u.event_type_id
join (select fun.eventtypeid ,fun.client_id ,uft.user_id
from vw_fund_queue fun
join uft_clnt uft on uft.uft_clnt_id = fun.client_id
) evt on evy.id = evt.eventtypeid
and u.user_id = evt.user_id
where evy.id = 1601 and u.user_id = 10061
union all
select u.id as id,evy.description as 'Work Description',count(*) as Pending
from user_event u
join event_type evy on evy.id = u.event_type_id
join (select fun.eventtypeid ,fun.client_id ,uft.user_id
from vw_fund_confirm fun
join uft_clnt uft on uft.uft_clnt_id = fun.client_id
) evt on evy.id = evt.eventtypeid
and u.user_id = evt.user_id
where evy.id = 1201 and u.user_id = 10061
union all
select u.id as id,evy.description as 'Work Description',count(*) as Pending
from user_event u
join event_type evy on evy.id = u.event_type_id
join (select fun.eventtypeid ,fun.client_id ,uft.user_id
from vw_fund_approve fun
join uft_user_clnt uft on uft.clnt_id = fun.client_id
) evt on evy.id = evt.eventtypeid
and uem.user_id = evt.user_id
where evy.id = 1202 and u.user_id = 10061 ) a where a.pending!=0
【问题讨论】:
-
甚至不是一个问题,只是一个提供建议的命令?
-
使用限制 1,您知道找到了一条记录
-
试试
EXPLAIN EXTENDED的力量。
标签: mysql sql performance select query-optimization