Create trigger on SQL Server table

Question

I want to create a trigger on a SQL Server table.

Table has 8 columns. One of them is email. i.e. peter@msn.com

What I want is: when a new row is inserted into the table, the trigger should update my ISP column with msn.com

  CREATE TRIGGER TIGUPDATEISP ON SUBS
  FOR INSERT
  AS 
     UPDATE SUBS 
     SET ISP = SELECT RIGHT(EMAIL, LEN(EMAIL) - CHARINDEX('@', EMAIL) FROM INSERTED)

This is updating all my isp with the last value. However, I wanted to update one as per insert.

Answer 1

This will work if the ISP column allows NULL values

CREATE TRIGGER TIGUPDATEISP ON Subs
   FOR INSERT
AS 
BEGIN

    SET NOCOUNT ON;

    UPDATE SUBS 
        SET ISP = (SELECT RIGHT(EMAIL, LEN(EMAIL) - CHARINDEX('@', EMAIL)) 
        FROM INSERTED
        WHERE SUBS.ID = INSERTED.ID)
    FROM INSERTED
    WHERE SUBS.Id = INSERTED.ID

END

This will work if the ISP column doesn't allow NULLS

CREATE TRIGGER TIGUPDATEISP ON Subs
   INSTEAD OF INSERT
AS 
BEGIN

    SET NOCOUNT ON;

    INSERT Subs (EMAIL, Isp)
    SELECT EMAIL, RIGHT(EMAIL, LEN(EMAIL) - CHARINDEX('@', EMAIL)) FROM INSERTED

END