> On Mar 6, 2015, at 9:58 AM, brian br...@meadows.pair.com [firebird-support] > <firebird-support@yahoogroups.com> wrote: > > My problem is that I must avoid duplicated records in the database, > the unique key is a complicated structure containing four 16-bit words > plus a 108-bit set of flags. The combination of the whole lot must be > unique. I don't need to retrieve this data other than to check for > duplicate records, so I can massage it in FreePascal so that it can go > into the database in any form that's desirable.
If there's any chance that you'll ever need data fromt the four 16-bit words, I'd create a five part primary key with four small integers followed by a 14 byte string octets. Firebird index keys are compressed and rearranged so they compare bytewise regardless of the original format - single field or multiple, combinations of strings and numbers, etc. If it were me, I'd let Firebird create the key from data. > > > If I were using PostgreSQL, I'd store the whole lot as a single > 172-bit bitstring, but I can't find any mention of an equivalent data > type in the Firebird documentation that I've been able to find. String of type octets works. > Good luck, Ann
