May be if we only have Sequence =1 for the particular PartNo, the record is considered unique.

>I don't get where Sequence comes into play here.
>
>>

>>PartId     PartNo  SerialNo     Sequence
>>1          AS345   ANB-121             1
>>2          AS345   ANB-122             2
>>3          AS345   ANB-123             3
>>4          AS345   ANB-124             4
>>5          A34SF   1212544             1
>>6          B21AC   ANB-A1              1
>>7          B21AC   ANB-A2              2
>>8          ANG34   ANG34               1
>>

>>
>>From the above set the query should return rows 5 and 8 because those partnumber/serialno combinations only appear once.
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>>>>I have a table of part information. The combination of PartNo and SerialNo make the row unique. There is a Sequence column.
>>>>I want to get back all records where there is only one record for PartNo/SerialNo combination. I'm not sure what the syntax
>>>>for this query is. Can someone help?
>>>
>>>Not sure what you want, could you please post some data and desired result from it?