动态更改别名

您需要动态生成该语句，并使用EXECUTE或sp_executesql执行该语句。

DECLARE   @i  INT ,          @l  INT ,          @desc  CHAr(50)SET @l = 1 SET @i = 20WHILE   ( @l <= @i ) BEGIN    EXEC ('SELECT  ''Test''   AS   Test'+@l)    SET @l =   @l  +  1END

进入动态SQL领域时的推荐阅读：动态SQL的诅咒和祝福

改用sp_executesql：

DECLARE   @i  INT ,          @l  INT ,          @desc  CHAr(50),          @SQL NVARCHAr(100)SET @l = 1 SET @i = 20WHILE   ( @l <= @i ) BEGIN    SET @SQL = N'SELECT  ''Test''   AS   Test'+CAST(@l AS NVARCHAr(10))    EXEC sp_executesql @SQL    SET @l =   @l  +  1END