T-SQL使用CTE递归

Posted 2020-09-09 高手皆寂寞-->何时才能寂寞呢?

DECLARE @DiGui TABLE ( Id INT, ParentId INT )
INSERT  INTO @DiGui
        ( Id ,
          ParentId 
        )
        SELECT  1 ,
                2
        UNION
        SELECT  2 ,
                3
        UNION
        SELECT  3 ,
                4
        UNION
        SELECT  5 ,
                10
        UNION
        SELECT  1 ,
                10
SELECT  *
FROM    @DiGui ;
WITH    temp ( [Id], [parentid] )
          AS ( SELECT   Id ,
                        parentid
               FROM     @DiGui
               WHERE    [Id] = 1
               UNION ALL
               SELECT   a.Id ,
                        a.parentid
               FROM     @DiGui a
                        INNER JOIN temp ON a.[Id] = temp.[parentid]
             )
    SELECT  *
    FROM    temp

　　结果：