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SELECT*FROM

`receivable_application_relation` d

WHERE d.`application_id` IN

(SELECT

id

FROM

application

WHERE application_code IN ('ZYHT20190305192721001','ZYHT20190309152839001','ZYHT20190309152904001'));

SHOW WARNINGS;

查看优化后最终执行的sql

In 并不是走的子查询 而是 join ，这个是 从上面的画红线的地方copy 出来的

SELECT

`cf_receivables_financing`.`d`.`id` AS `id`,

`cf_receivables_financing`.`d`.`application_id` AS `application_id`,

`cf_receivables_financing`.`d`.`receivable_id` AS `receivable_id`,

`cf_receivables_financing`.`d`.`update_time` AS `update_time`,

`cf_receivables_financing`.`d`.`create_time` AS `create_time`,

`cf_receivables_financing`.`d`.`deleted` AS `deleted`

FROM

`cf_receivables_financing`.`application`

JOIN `cf_receivables_financing`.`receivable_application_relation` `d`

WHERE (

(

`cf_receivables_financing`.`d`.`application_id`=`cf_receivables_financing`.`application`.`id`

)

AND (

`cf_receivables_financing`.`application`.`application_code` IN ('ZYHT20190305192721001','ZYHT20190309152839001','ZYHT20190309152904001')

)

)

EXPLAIN EXTENDED

SELECT

d.*FROM

`receivable_application_relation` d

INNER JOIN application a

ON d.`application_id`=a.id

WHERE a.application_code IN ('ZYHT20190305192721001','ZYHT20190309152839001','ZYHT20190309152904001');

查看优化后的sql

SELECT

`cf_receivables_financing`.`d`.`id` AS `id`,

`cf_receivables_financing`.`d`.`application_id` AS `application_id`,

`cf_receivables_financing`.`d`.`receivable_id` AS `receivable_id`,

`cf_receivables_financing`.`d`.`update_time` AS `update_time`,

`cf_receivables_financing`.`d`.`create_time` AS `create_time`,

`cf_receivables_financing`.`d`.`deleted` AS `deleted`

FROM

`cf_receivables_financing`.`receivable_application_relation` `d`

JOIN `cf_receivables_financing`.`application` `a`

WHERE (

(

`cf_receivables_financing`.`d`.`application_id`=`cf_receivables_financing`.`a`.`id`

)

AND (

`cf_receivables_financing`.`a`.`application_code` IN ('ZYHT20190305192721001','ZYHT20190309152839001','ZYHT20190309152904001')

)

);