通过单个查询获取表数据 [英] fetching table data with single query

问题描述

我想访问name ='vehicle'下的所有数据，因此所有子级和子级子都应在单个查询中

I want to access all data under name='vehicle' so all child's and sub child's should get in single query

我已经尝试过该查询

SELECT a.CID as MainCategoryID, b.CID as ChildCategoryID, b.parentID
FROM categories a, categories b
WHERE a.CID = b.parentID AND NAME='vehicle'

推荐答案

可能的解决方案如下:

SELECT @pv:=cid AS 'cid', name, parentID FROM categories
JOIN (SELECT @pv:=0) tmp
WHERE parentID = @pv

您可以在此处找到SQLFiddle: http://www.sqlfiddle.com/# ！2/6c75a0/6

you can find a SQLFiddle here: http://www.sqlfiddle.com/#!2/6c75a0/6

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