Mysql 查询优化_Mysql_Query Optimization

Mysql 查询优化

mysql

Mysql 查询优化,mysql,query-optimization,Mysql,Query Optimization,有没有办法优化这个查询，使之更快 SELECT id FROM business WHERE id NOT IN(SELECT business_id FROM business_community GROUP BY business_id) 试试这个： SELECT id FROM business AS b LEFT JOIN business_community bc ON bc.business_id = b.id WHERE bc.business_id IS NULL 可能使用

有没有办法优化这个查询，使之更快

SELECT id FROM business 
WHERE id NOT IN(SELECT business_id FROM business_community GROUP BY business_id)

试试这个：

SELECT id FROM business AS b
LEFT JOIN business_community bc ON bc.business_id = b.id
WHERE bc.business_id IS NULL

可能使用“DISTINCT business_id”而不是Groupby.

我不确定左连接后再进行

NULL

检查是否会更快，但我认为值得尝试。仅供参考，这是mysql中的一个错误->