INNER JOIN 之前的 WHERE 子句

2021-12-17 00:00:00 join optimization where mysql

如果我有

SELECT * FROM Table1 t1 
LEFT JOIN Table2 t2 ON t1.id = t2.id 
WHERE t1.user='bob';

WHERE 子句是否在两个表 JOINED 之后运行?

Does the WHERE clause run after the two tables are JOINED?

如何使它在 JOIN 之前运行?

How do I make it so it runs prior to the JOIN?

推荐答案

将WHERE改成另一个JOIN条件

LEFT JOIN Table2 t2 on t1.id = t2.id AND t1.user='bob'

相关文章