An SQL problem really, but I am only interested in a Firebird centric solution ;)

I have extended a section so allow filtering of a list of records based on a
number of 'tags' where these are stored as a set of detail records, but I'm
struggling with getting a list of results which have a single entry per item.

Detail record has alphanumeric key like '$00', $01', $02'... and I need to limit
the master list to say 'where detail key in ('$00', '$02')'. This should be
easy, but I'm having a bit of a block to the thought process at present :(

--
Lester Caine - G8HFL
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