First, replace 'mytable' with 'PartHistory' and 'PartNo' with 'PartId'. After that you can use result set as derived table and join back to Parts on PartId.

>Ok, I get it. But there's a catch
>
>PartNo is in Parts. The remain data is in PartHistory:
>
>

>CREATE TABLE Parts
>	(PartId		INT IDENTITY PRIMARY KEY,
>	 PartNo		VARCHAR(30)	NOT NULL,
>	 Description	TEXT		NOT NULL)
>
>CREATE TABLE PartHistory
>	(HistoryId	INT IDENTITY PRIMARY KEY,
>	 PartId		INT		NOT NULL,
>	 UserId		INT		NOT NULL,
>	 LocationId	INT		NULL,
>	 SerialNo	VARCHAR(30)	NULL,
>	 Quantity	INT		NOT NULL,
>	 DropShip	TINYINT		NULL,
>	 Printed	TINYINT		NULL,
>	 ActionDate	DATETIME	NULL DEFAULT GETDATE(),	
>	 Sequence	INT		NOT NULL,
>	 Comments	TEXT		NULL)
>
>

>
>So, given this, how do I join these tables in this query you gave me?
>
>
>>Try

>>-- or 
>>SELECT * FROM mytable mt1
>>  WHERE NOT EXISTS (SELECT 1 FROM mytable mt2 
>>                  WHERE mt1.PartNo = mt2.PartNo AND mt1.SerialNo = mt2.SerialNo
>>                    AND mt1.Sequence < mt2.Sequence)
>>- or
>>SELECT * FROM mytable mt1
>>  WHERE 1 =  (SELECT COUNT(*)  FROM mytable mt2 
>>                  WHERE mt1.PartNo = mt2.PartNo AND mt1.SerialNo = mt2.SerialNo)
>>
>>- or (may not work because of NULL date)
>>SELECT * FROM mytable mt1
>>  WHERE NOT EXISTS (SELECT 1 FROM mytable mt2 
>>                  WHERE mt1.PartNo = mt2.PartNo AND mt1.SerialNo = mt2.SerialNo
>>                    AND mt1.Date <> mt2.Date)
>>

>