Interesting. Can you point me to some simple article explaining indexes type in SQL Server? I don't have SQL installed on my PC, so direct link would be great.

Thanks a lot in advance.

>I'm guessing the biggest advantage to 3 is that option 2 has an extra index that is being maintained for no reason. The one on lineID by itself might never be used.
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>Thanks again for the reply.
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>>I think so. But I think using invoice no. in primary key, since it will be part of the primary method of selecting recs also helps.
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