Question

我有一个SQL表，它由两列没有列id组成，两列是汽车等效部分的组合，需要在一列中返回所有可能的关系，给出一列或另一列的元素，例如，给定值是530：

 ColunaA    ColunaB 
 530          520
 530          510
 530          444
 444          222
 333          111

最终结果必须是：

我尝试了这个SQL查询：

WITH AreasCTE AS 
(
 SELECT colunaa, colunab FROM dbo.Tabela1 WHERE colunaa = '530' 
 UNION ALL 
 SELECT a.colunaa, a.colunab FROM dbo.Tabela1 a 
 INNER JOIN AreasCTE s ON a.colunaa = s.colunaa
) 
SELECT top 100 colunaa, colunab FROM AreasCTE

感谢您的帮助!!

Answer 1

试试这个，它不是完美的解决方案可能需要一些性能调整，但应该完成这项工作。

    DECLARE @t1 TABLE
    (
        colunaA NVARCHAR(MAX) ,
        colunaB NVARCHAR(MAX)
    );

INSERT INTO @t1
VALUES ( 530, 520 ) ,
       ( 530, 510 ) ,
       ( 530, 444 ) ,
       ( 444, 222 ) ,
       ( 333, 111 );

SELECT *
FROM   @t1;

DECLARE @value NVARCHAR(MAX);
SET @value = 222;

DECLARE @filter TABLE
    (
        id NVARCHAR(MAX)
    );

INSERT INTO @filter
VALUES ( @value );

DECLARE @right_row_count INT;
DECLARE @left_row_count INT;

SET @left_row_count = 1;


WHILE @left_row_count > 0
      OR @right_row_count > 0
    BEGIN

        INSERT INTO @filter ( id )
                    SELECT DISTINCT t.colunaA
                    FROM   @t1 t
                           INNER JOIN @filter f ON t.colunaB = f.id
                    WHERE  t.colunaA NOT IN (   SELECT *
                                                FROM   @filter );
        SET @right_row_count = @@rowcount;

        INSERT INTO @filter ( id )
                    SELECT DISTINCT t.colunaB
                    FROM   @t1 t
                           INNER JOIN @filter f ON t.colunaA = f.id
                    WHERE  t.colunaB NOT IN (   SELECT *
                                                FROM   @filter );
        SET @left_row_count = @@rowcount;


    END;

SELECT   *
FROM     @filter
ORDER BY id DESC;

多少个SQL关系仅提供一个元素

1 个答案: