SELECT DATE(del_sendmsg_records.send_date) AS oneday,del_branchs.name AS del_branch_name, del_branchs.shortname AS del_branch_shortname, COUNT(*) AS number
FROM del_sendmsg_records
JOIN del_branchs
ON del_sendmsg_records.del_branch_id=del_branchs.id
WHERE del_sendmsg_records.sended=1
GROUP BY oneday,del_sendmsg_records.del_branch_id
這個應該怎么優化啊，目測是因為這個才慢WHERE del_sendmsg_records.sended=19（sendedtinyint(1) NOT NULL是否已發送，0未發送，1發送）應該怎么優化
uj5u.com熱心網友回復：
uj5u.com熱心網友回復：
關聯表的順序換下 分組欄位順序換下 建立復合索引（sended del_branch_id） 試下吧 看有沒有效果 正常應該是弄個統計表的uj5u.com熱心網友回復：
設定表別名 你試一試轉載請註明出處，本文鏈接：https://www.uj5u.com/shujuku/92430.html
標籤：MySQL
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