各路大神,我这个SQL感觉查询出来数据速度特别慢啊,要全部查询出来要120多秒,然后想建立索引,但是发现建立索引并不能优化多少,有没有其他方法可以给到优化呢?感谢各位了!!!
SELECT T1.*,
c.COMPANY_NAME AS companyShortName FROM
(
SELECT i.*, o.SUP_COMPANY_SAP_CODE AS companyCode FROM
(
SELECT * FROM T_BASE_PUR_ORDER where PROJECT_ID='6' and COMPANY_ID= '20170623111117-7147d39a28ad40e8a'
) o,T_BASE_PUR_ORDER_ITEM i WHERE i.order_id = o.ID AND i.IS_ENABLE = 1
) T1
LEFT JOIN T_BASE_COMPANY c ON c. ID = T1.PUR_COMPANY_ID