sqlserver id相同的多行合並為一行，用逗號分隔

單表操作

創建測試表city：

把cityLevel相同的cityName合並在一起用逗號分隔 如：北京,上海,廣州

SELECT cityLevel,
cityName =stuff(
(select ','+cityName FROM city WHERE cityLevel = c.cityLevel for xml path(''))
,1,1,'')
FROM city c
group by cityLevel

用city表和一張新的city命名為c,匹配cityLevel相同的項目,然后用cityLevel進行分組

兩表操作

將city表拆開

citys:

city:

SELECT temp2.cityLevel,
cityName =stuff(
(select ','+cityName FROM 
(select cs.cityLevel,cs.cityId,c.cityName from citys as cs inner join city as c on cs.cityId = c.id) temp
WHERE temp.cityLevel = temp2.cityLevel for xml path(''))
,1,1,'')
FROM (select cs.cityLevel,cs.cityId,c.cityName from citys as cs inner join city as c on cs.cityId = c.id) temp2
group by temp2.cityLevel