對于這種情況,我在 PHPMyAdmin 中有三個使用 mysql 的表。第一個是Provice,第二個是City,第三個是User。
Province table:
id name
--------------
1 province1
2 province2
3 province3
City table:
id name
------------
1 city1
2 city2
3 city3
User table:
id name addressB cityA provinceA addressB cityB provinceB
----------------------------------------------------------------------------------
1 Adam Mango street 1 1 banana street 2 1
2 Antonio Peach street 3 2 banana street 2 1
我的問題是:我如何使用查詢加入省和城市表以得到這樣的結果:
id name addressA cityA provinceA addressB cityB provinceB
-------------------------------------------------------------------------------------
1 Adam Mango street city1 province1 banana street city2 province1
2 Antonio Peach street city3 province2 Guava street city2 province1
我應該將用戶表中的 CityA、CityB、ProvinceA 和 ProvinceB 拆分為一個獨立的表嗎?或者有一個或一些我以前從未想過的問題?
uj5u.com熱心網友回復:
查詢需要為每列加入一次參考表
select
a.*, ca.name cityA, cb.name cityB, pa.name provinceA, pb.name provinceB
from user_table a
join city_table ca on a.cityA = ca.id
join city_table cb on a.cityB = cb.id
join province_table pa on a.provinceA = pa.id
join province_table pb on a.provinceB = pb.id
;
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標籤:mysql sql phpmyadmin
