sorrry, late tired. first name 20, not 23 Cheers,
Ann > On Nov 30, 2014, at 8:38 PM, Ann Harrison <aharri...@nimbusdb.com> wrote: > > > >> On Nov 30, 2014, at 6:35 PM, Stuart Simon <stuart...@gmail.com> wrote: >> >> OK, but version numbers tell me nothing. What I am looking for is an >> explanation of how Firebird (the package) can tell which bytes belong to >> which fields. Somehow Firebird must be able to tell the difference between >> the following two records: >> >> FirstName LastName >> 'Jim' 'Starkey' >> 'Jim Starkey' '' >> >> >> It may well be that it was coded in the Interbase days and has not been >> looked up until now. Or maybe it's the blob in the "RDB$DESCRIPTOR" field, >> in which case I do not know how to decode it into text. > > No. The format of the record is included in the record header, which is > described in ods.h. Use that number to look up the record in RDB$FORMATS. > That tells you how long each field is - uncompressed. On disk, each record > is compressed using a run lenth compression of the whole record. The first > byte is a length. If it's positive, the next <n> bytes are data. If > negiative, the next <n> bytes are the following byte value. E.g. 0x3, > 'Jim', 0x-20, ' ', 0x7, 'Starkey', 0x23, ' ' etc. would be Jim(17 > spaces)Starkey. That would correspond to FirstName 23, LastName 30. > > Good luck, > > Ann ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
