SQL Sever中使用SQL语句实现把重复行数据合并为一行并用逗号分隔
一.定义表变量
DECLARE@T1table ( UserIDint, UserNamenvarchar(50), CityNamenvarchar(50) );
insertinto@T1(UserID,UserName,CityName)values(1,'a','上海') insertinto@T1(UserID,UserName,CityName)values(2,'b','北京') insertinto@T1(UserID,UserName,CityName)values(3,'c','上海') insertinto@T1(UserID,UserName,CityName)values(4,'d','北京') insertinto@T1(UserID,UserName,CityName)values(5,'e','上海')
select*from@T1
-----最优的方式 SELECTCityName,STUFF((SELECT','+UserNameFROM@T1subTitleWHERECityName=A.CityNameFORXMLPATH('')),1,1,'')ASA FROM@T1A GROUPBYCityName
----第二种方式 SELECTB.CityName,LEFT(UserList,LEN(UserList)-1) FROM( SELECTCityName,(SELECTUserName+','FROM@T1WHERECityName=A.CityNameFORXMLPATH(''))ASUserList FROM@T1A GROUPBYCityName )B
stuff(select','+fieldname fromtablenameforxmlpath('')),1,1,'')