If records in NET belongs to both periods, it'll show only once. Create separate queries for current period and previous period and UNION ALL them.

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>Funny, I could have sworn I replied to your last (I certainly wrote it down)
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>Your idea with the operator code has certainly restricted the results to one op. - great.
>That and the soln. below, though, still give wrong results.
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>For my selected op, for the 2 time periods: curr. and prev., I should be getting 3 matching recs each.
>I'm getting the 1st record from the prev period OK, but not the other 2, and the 2nd & 3rd recs OK from the curr operiod, but not the 1st. They're excluding each other.
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