Question

I have a trigger that supposed to update log out time[generate random log out time within an hour of log in time, seconds have to differ too], how do I achieve that functionality, please help here is my trigger so far:

USE TestDB
GO
CREATE TRIGGER AfterInsertTG
ON dbo.usage_reports_Dummy2
AFTER INSERT AS

    DECLARE @pk_id as int, @member_id as int,@login_time AS DATETIME,@logout_time AS DATETIME
    ,@ip AS VARCHAR(255),@session_id AS VARCHAR(255);
    SELECT 
        @pk_id = pk_id ,
        @member_id = member_id,
        @login_time =login_time,
        @logout_time = logout_time,
        @ip = ip,
        @session_id = session_id
    FROM
        usage_reports_Dummy2


    IF(@logout_time IS NULL)

        BEGIN
        ??????? 
        END     

GO

Thank you all for helping me out specially Eric for taking some time and think about the formula, I chose Marc’s answer becuase it suits my conditions

here is the final code:

CREATE TRIGGER trgInsert
ON dbo.usage_reports_Dummy2
INSTEAD OF INSERT
AS BEGIN
    INSERT INTO 
       dbo.usage_reports_Dummy2(member_id, login_time, logout_time, ip, session_id)
          SELECT 
             member_id, login_time, logout_time, ip, session_id
          FROM inserted 
          WHERE logout_time IS NOT NULL

    INSERT INTO 
       dbo.usage_reports_Dummy2(member_id, login_time, logout_time, ip, session_id)
          SELECT 
              member_id, login_time, DATEADD(ss, RAND() * 3600, login_time), 
              ip, session_id
          FROM inserted 
          WHERE logout_time IS NULL
END

Answer 1

What you could do is create an INSTEAD OF INSERT trigger something like this:

CREATE TRIGGER trgInsert
ON dbo.usage_reports_Dummy2
INSTEAD OF INSERT
AS BEGIN
    INSERT INTO 
       dbo.usage_reports_Dummy2(member_id, login_time, logout_time, ip, session_id)
          SELECT 
             member_id, login_time, logout_time, ip, session_id
          FROM inserted 
          WHERE logout_time IS NOT NULL

    INSERT INTO 
       dbo.usage_reports_Dummy2(member_id, login_time, logout_time, ip, session_id)
          SELECT 
              member_id, login_time, DATEADD(ss, RAND() * 3600, login_time), 
              ip, session_id
          FROM inserted 
          WHERE logout_time IS NULL
END

That way, if a “logout_time” is provided, the values are stored “as is”, and if not, then your logout_time is calculated based on your requirements.

Marc