MySQL-从多个具有相同结构但数据不同的表中选择数据 [英] MySQL - Selecting data from multiple tables all with same structure but different data

问题描述

好吧，这是我的两难选择.我有一个数据库，其中包含约5个表，它们的数据结构完全相同.出于本地化目的，以这种方式分离了数据，并总共分割了约450万条记录.

Ok, here is my dilemma I have a database set up with about 5 tables all with the exact same data structure. The data is separated in this manner for localization purposes and to split up a total of about 4.5 million records.

在大多数情况下，只需要一张桌子就可以了.但是，有时需要两个或两个以上表中的数据，并且需要按用户定义的列对其进行排序.这就是我遇到的问题.

A majority of the time only one table is needed and all is well. However, sometimes data is needed from 2 or more of the tables and it needs to be sorted by a user defined column. This is where I am having problems.

数据列:

id, band_name, song_name, album_name, genre

MySQL声明:

SELECT * from us_music, de_music where `genre` = 'punk'

MySQL吐出此错误:

MySQL spits out this error:

#1052 - Column 'genre' in where clause is ambiguous

很明显，我做错了.有人愿意为我阐明一下吗?

Obviously, I am doing this wrong. Anyone care to shed some light on this for me?

推荐答案

我认为您正在寻找

I think you're looking for the UNION clause, a la

(SELECT * from us_music where `genre` = 'punk')
UNION
(SELECT * from de_music where `genre` = 'punk')

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