Question

我有一个包含多列的表（dbo.membersdatatable）。我想这个触发器更新一个名为＆＃34; memberstatus＆＃34;的列。什么时候＆＃34;会员指定＆＃34;更新为＆＃34; 10＆＃34;来自＆＃34; 9＆＃34;。

的值

-------下面的SQL语句---------------

IF UPDATE([MemberDesignation])
--need to make it so it will recognize when memberdesignation = 10 
    UPDATE      dbo.MembersDataTable
    SET     MemStatus = '0'
    FROM        dbo.MembersDataTable AS mdtbl
    INNER JOIN  inserted AS i ON i.StudentID = mdtbl.StudentID

Answer 1

使用SPARINGLY触发器。例如，我的系统有138个表，550个存储过程，只有28个触发器。我希望自己少一点。

但如果您决定需要触发器，它将如下所示：

CREATE TRIGGER [t_MemberDesignationSideEffect] ON [dbo].MembersDataTable
FOR UPDATE 
AS

SET NOCOUNT ON  

IF NOT (    UPDATE([MemberDesignation])  ) RETURN

-- REMINDER: All triggers can and will fire for a set of rows...not just one

UPDATE mdtbl
SET     MemStatus = '0'
FROM  inserted i 
    JOIN dbo.MembersDataTable mdtbl on i.StudentID = mdtbl.StudentID
    JOIN deleted d on d.StudentID = mdtbl.StudentID
WHERE i.memberdesignation = '10'
and d.memberdesignation = '9'

GO

Answer 2

您正在桌面上编写更新触发器。在这里，您可以使用已删除和插入的魔术表。如果是更新触发器：

已删除表包含UPDATE语句之前的行。 插入的表包含行，因为它在语句之后。

create trigger update_member_status
on membersdatatable
for update
as
begin
    declare @old_designation int
    declare @new_designation int

    set @old_designation = (select memberdesignation from deleted)
    set @new_designation = (select memberdesignation from inserted)

    if (@old_designation = 9 and @new_designation = 10)
        begin
            update membersdatatable 
            set memstatus = '0'
            from membersdatatable as mdtbl
                inner join inserted as i on i.StudentID = mdtbl.StudentID
        end
end

Answer 3

您将使用a更新所有行的成员状态 memberdesignation = 10

您可以为此查询添加条件，以便仅使用日期字段或其他字段更新所需的条件

更新表格后，只需调用此程序

CREATE PROCEDURE USP_MemberStatusRules()
AS
    UPDATE      dbo.MembersDataTable
    SET     MemStatus = '0'
    WHERE memberdesignation = 10
    AND .....
    AND .....
GO

更新触发器后的SQL Server - 单个表 - 2列

3 个答案: