Question

亲爱的，我的触发器遇到了麻烦。

我是否正在这样做，现在它只适用于Insert。我想我很亲密，如果你有时间，请帮助我。我试图通过触发器将所有插入，更新和删除存储到表customers_changelog中。我无法删除或更新客户的代码有问题我只能插入新的代码。请帮助我，我已经花了很多时间在这上面，只是不能让这个工作！：）

create table customers (
customerid int identity primary key,
name varchar(100) not null,
address varchar(100)
)
go

create table customers_changelog (
customerid int,
name varchar(100) not null,
address varchar(100),
change_user varchar(32),
change_time datetime,
change_action char(1) default 'I',
check (change_action = 'I' or change_action = 'D')
)
go


CREATE TRIGGER log_changes
ON customers
AFTER INSERT, UPDATE, DELETE
AS 
BEGIN
    SET NOCOUNT ON;

--
-- Check if this is an INSERT, UPDATE or DELETE Action.
-- 
DECLARE @customerid1 as int;
DEClARE @name1 as varchar(32);
DECLARE @address1 as varchar(100);
DECLARE @change_action1 as char(1);
DECLARE @change_time1 as datetime;
DECLARE @change_user1 as varchar(32);

select  @customerid1 = c.customerid, @name1 = c.name, @address1 = c.address
from customers c, inserted i
where c.customerid = i.customerid 

SET @change_time1 = CURRENT_TIMESTAMP;
SET @change_user1 = CURRENT_USER;
INSERT INTO customers_changelog(customerid,name,address,change_action,change_time,change_user)
    VALUES(@customerid1,@name1,@address1,'I',@change_time1,@change_user1)
IF EXISTS(SELECT * FROM DELETED)
BEGIN    
            IF EXISTS(SELECT * FROM INSERTED) 
            INSERT INTO customers_changelog VALUES(@customerid1,@name1,@address1,'U',@change_time1,@change_user1)
            ELSE 
            INSERT INTO customers_changelog VALUES(@customerid1,@name1,@address1,'D',@change_time1,@change_user1)

END
ELSE 
    IF NOT EXISTS(SELECT * FROM INSERTED) RETURN;
END

Answer 1

假设MS-SQL来自语法 - 所以这里有几个问题：
1.需要在“更新”和“删除”插入中指定列列表，因为表中的列顺序与您的插入不匹配。
2.不能使用“插入”数据进行删除插入

ALTER TRIGGER [dbo].[log_changes] ON [dbo].[customers] AFTER INSERT, UPDATE, DELETE AS 
BEGIN
    SET NOCOUNT ON;
    DECLARE @customerid1 as int;
    DEClARE @name1 as varchar(32);
    DECLARE @address1 as varchar(100);
    DECLARE @change_action1 as char(1);
    DECLARE @change_time1 as datetime;
    DECLARE @change_user1 as varchar(32);

    select  @customerid1 = c.customerid, @name1 = c.name, @address1 = c.address
    from customers c, inserted i
    where c.customerid = i.customerid 

    SET @change_time1 = CURRENT_TIMESTAMP;
    SET @change_user1 = CURRENT_USER;

    IF EXISTS(SELECT * FROM DELETED)
    BEGIN    
                IF EXISTS(SELECT * FROM INSERTED) 
                INSERT INTO customers_changelog(customerid,name,address,change_action,change_time,change_user) 
                    VALUES(@customerid1,@name1,@address1,'U',@change_time1,@change_user1)
                ELSE 
                BEGIN
                    select  @customerid1 = d.customerid, @name1 = d.name, @address1 = d.address
                        from deleted d
                    INSERT INTO customers_changelog(customerid,name,address,change_action,change_time,change_user) 
                        VALUES(@customerid1,@name1,@address1,'D',@change_time1,@change_user1)
                END

    END
    ELSE
    BEGIN
        IF NOT EXISTS(SELECT * FROM INSERTED) RETURN;
        INSERT INTO customers_changelog(customerid,name,address,change_action,change_time,change_user)
            VALUES(@customerid1,@name1,@address1,'I',@change_time1,@change_user1) 
    END
END

插入更新删除触发器

1 个答案: