Question

我是初学程序员。这是我的表结构：

Database structure

我想从'post'表中检索内容并输入字段，其中userdId跟在'following'字段后面。我正在尝试这个SQL Join来追踪追随者。

SELECT userId,following, userId,postId,content,file,type
FROM follow, post
WHERE userId = '5a37589e4ff8b'

Answer 1

您应该使用JOIN语法

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    <table id="table1" align="center" border="1" width="800" cellpadding="0" cellspacing="0">
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如何对下表执行连接操作？

1 个答案: