Linux 连接表，-规范化字段
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Joining Tables,- Normalizing Fields
提问by Q2Ftb3k
I have two tables. One table is named "Posts", the other is "Threads". Each of these has 3 columns named (id, author, content). The Posts table has a specific (thread) column. The thread column has to correspond to the id in the Threads table. What I'm trying to do is make one query that will select the thread, and all of its posts, and normalize its resulting fields. Here is what I want to generate:
我有两张桌子。一张表名为“Posts”，另一张表名为“Threads”。其中每一个都有 3 个名为（id、作者、内容）的列。Posts 表有一个特定的（线程）列。线程列必须对应于线程表中的 id。我正在尝试做的是进行一个查询，该查询将选择该线程及其所有帖子，并对其结果字段进行规范化。这是我想要生成的内容：
author | content
作者 | 内容
Person| This is the thread's contents
Person| This would be a post.
Person| And another post.
人| 这是线程的内容
人| 这将是一个帖子。
人| 还有一个帖子。
回答by smdrager
"Normalize its resulting fields"? I'm not sure what you mean by that. Also you contradicted yourself saying both have three fields, but that Posts has a fourth field (foreign key to Threads)?
“标准化其结果字段”？我不确定你的意思。您还自相矛盾，说两者都有三个字段，但 Posts 有第四个字段（线程的外键）？
Also you really probably don't want to do that in one query (it would be far from "normalized"
此外，您可能真的不想在一个查询中这样做（这远非“规范化”
SELECT * FROM Threads WHERE id = @id
SELECT * FROM Posts WHERE thread = @threads
Alternatively,
或者，
SELECT * FROM Posts LEFT JOIN Threads ON Posts.thread = Thread.id WHERE Posts.thread = @thread
