连接表上的SQL Case条件

Question

我需要使用大小写条件修改此sql，我需要所有模型都可以回显，但只有在满足where条件的情况下才可以回显tw。 最好的方法是什么？

SELECT * FROM model
LEFT OUTER JOIN tw
ON model.model_name=tw.model
WHERE tw.completed = 1 AND tw.stock = 0
ORDER BY model.id

Answer 1

我认为您只需要将where条件移到on子句：

SELECT m.*, t2.*
FROM model m LEFT OUTER JOIN
     tw
     ON m.model_name = tw.model AND
        tw.completed = 1 AND tw.stock = 0
ORDER BY m.id;