MySQL 中逗号分隔的连接和语法上的连接有什么区别?

What#39;s the difference between comma separated joins and join on syntax in MySQL?(MySQL 中逗号分隔的连接和语法上的连接有什么区别?)

问题描述

例如，如果我有一个表Person"，其中一个id"列引用了Worker"表中的id"列

For example if I were to have a table "Person" with a column "id" that references a column "id" in table "Worker"

这两个查询之间的区别是什么?它们产生相同的结果.

What would the difference between these two queries be? They yield the same results.

SELECT * 
FROM Person 
JOIN Worker 
  ON Person.id = Worker.id;

和

SELECT * 
FROM Person, 
     Worker 
WHERE Person.id = Worker.id;

谢谢

推荐答案

完全没有区别.

第一种表示使查询更具可读性，并且可以很清楚地看出哪个连接对应哪个条件.

First representation makes query more readable and makes it look very clear as to which join corresponds to which condition.

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