使用递归循环层次结构的T-SQL存储过程 [英] T-SQL Stored Procedure for Looping a hierarchy with recursion

问题描述

我有一个具体的问题.

我的存储过程无法正常工作..我将向您显示过程，数据库和参数:

My Stored Procedure don't work correctly.. I will show you the Procedure, the database and the parameter:

ALTER PROCEDURE [dbo].[ManufacturerParentToChild] 

@ServiceProviderId int,
@CarmakerId int

AS 开始

SET NOCOUNT ON;

DECLARE @childSPPId int, @isDeleted bit

DECLARE ServiceProviderChildren_Cursor CURSOR FOR

SELECT ServiceProviderId, isDeleted
FROM ServiceProvider 
WHERE ParentServiceProviderId = @ServiceProviderId; 

OPEN ServiceProviderChildren_Cursor;

FETCH NEXT FROM ServiceProviderChildren_Cursor INTO @childSPPId, @isDeleted;

WHILE @@FETCH_STATUS = 0
   BEGIN
        IF @ServiceProviderId > 0
        BEGIN
            EXEC ManufacturerParentToChild @childSPPId, @CarmakerId;

            IF (SELECT COUNT(*) FROM dbo.CarmakerPartnership WHERE ServiceProviderId = @childSPPId AND CarmakerId = @CarmakerId) = 0
            BEGIN
                IF (@isDeleted = 0)
                BEGIN
                    INSERT INTO dbo.CarmakerPartnership (CarmakerId, ServiceProviderId, CreatedBy, ChangedBy, ValidityPeriodFrom, ValidityPeriodTo) VALUES (@CarmakerId, @childSPPId, SYSTEM_USER, SYSTEM_USER, '01.01.1900 00:00:00', '31.12.9999 23:59:00.000')
                END
            END 
        END
      FETCH NEXT FROM ServiceProviderChildren_Cursor INTO @childSPPId;
   END;
CLOSE ServiceProviderChildren_Cursor;
DEALLOCATE ServiceProviderChildren_Cursor; END

您在上面看到了我的存储过程.

You See my stored Procedure above.

数据库表服务提供者有7行:

The Database Table Service Provider have 7 Rows:

ServiceProviderId名称ParentServiceProviderId已删除
1'Parent'Null 0
2'Child1'1 0
3'Child2'1 0
4'Child4'2 0
5'Child5'3 0
6'child6'4 0
7'Child7'6 0

ServiceProviderId Name ParentServiceProviderId isDeleted
1 'Parent' Null 0
2 'Child1' 1 0
3 'Child2' 1 0
4 'Child4' 2 0
5 'Child5' 3 0
6 'child6' 4 0
7 'Child7' 6 0

参数获取值:

@ServiceProviderId = 1 @CarmakerId = 5

@ServiceProviderId = 1 @CarmakerId = 5

该过程将ServiceProviderId 7、6、4和2插入CarmakerPartnerShip中，但不要插入3和5！

The Procedure insert the ServiceProviderId 7, 6, 4 and 2 into CarmakerPartnerShip but don't insert 3 and 5!

任何人都知道为什么递归循环跳过ServiceProviderId = 2的子代，却不跳过ServiceProviderId = 3的子代吗?

Have anybody a idea why the recursive loop jump trough the childs of ServiceProviderId = 2 but don't jump trough the childs of ServiceProviderId = 3 ??

谢谢您的帮助，抱歉我的英语不好！

Thank you for your Help and Sorry for my bad english!!

如果您有任何疑问，可以问我.

If you have Questions you can ask me.

最好的问候

亚历克斯

推荐答案

while块中的fetch语句可能是原因.目前显示为:

The fetch statement in the while block may be the cause. Currently it reads:

FETCH NEXT FROM ServiceProviderChildren_Cursor INTO @childSPPId;

尝试将其替换为:

FETCH NEXT FROM ServiceProviderChildren_Cursor INTO @childSPPId, @isDeleted;

这篇关于使用递归循环层次结构的T-SQL存储过程的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！