Question

我有表名称被称为小部件，并且有删除触发器。当我删除一个特定的行时，我想要删除其他具有重新签名的行

触发器

ALTER TRIGGER [dbo].[Trigger_sys_widgets_Delete]
   ON  [dbo].[sys_widgets]
   AFTER DELETE
AS 
BEGIN
    Delete From sys_Widgets Where parent in (Select id From deleted);
END

但是这不会删除其他行只删除第一行！

我可以在Depete循环中使此触发器工作，直到相对Childs中没有任何内容

还尝试级联删除

Alter Table sys_widgets Add Constraint FK_sys_widgets foreign Key (parent) References sys_widgets(id) On Delete Cascade;

这可能是为同一个表做的吗

Answer 1

您可以使用递归CTE通过一次触发运行删除所有子项。

ALTER TRIGGER [dbo].[Trigger_sys_widgets_Delete]
    ON  [dbo].[sys_widgets]
    AFTER DELETE
AS 
BEGIN
    WITH ForDelete AS
    (
        SELECT widgets.id
        FROM [dbo].[sys_widgets] AS widgets
        INNER JOIN deleted ON widgets.parent = deleted.id
        UNION ALL
        SELECT widgets.id
        FROM [dbo].[sys_widgets] AS widgets
        INNER JOIN ForDelete ON widgets.parent = ForDelete.id
    )
    DELETE FROM [dbo].[sys_widgets]
    WHERE id in (SELECT id FROM ForDelete);
END

Ms sql Trigger - 可以删除触发器影响还删除了行触发器

1 个答案: