Duplicate record trigger

This is part of my trigger on table T1. I am trying to check if the records inserted to T1 is available in myDB.dbo.myTable or not (destination table). If it is available rollback T1. It does not do that although I insert the same records twice.

-- duplicate record check

SET @.step = 'Duplicate record'

IF EXISTS (

SELECTi.myID, i.Type

FROMINSERTED i INNER JOIN

myDB.dbo.myTable c ON i.myID = c.myID

GROUP BY i.myID, i.Type

HAVING(COUNT(*) > 1) AND (i.Type = 'In')

)

BEGIN

ROLLBACK transaction

RAISERROR('Error: step: %s.rollback is done.', 16, 1, @.step)

Return

END

What is problem?

Moving to the T-SQL forum.|||
IF EXISTS (SELECT *
FROM inserted i
JOIN T1 T ON i.id = T1.id AND i.type = T1.type
)
BEGIN
ROLLBACK TRANSACTION
RAISERROR('Duplicate Values Entered.', 16, 1)
RETURN
ENDsql