Subject RE: [firebird-support] Re: copying data between FB DBs on the sam e machine
Author Brenden Walker
> -----Original Message-----
> From: christian_stengel [mailto:christian_stengel@...]
> Sent: Tuesday, August 12, 2003 10:44 AM
> To:
> Subject: [firebird-support] Re: copying data between FB DBs
> on the same machine
> Hi,
> maby, if you really just want to copy some data
> between two databases (and you don't need to do this
> concurrenty and permanently) you can declare an table as an
> external file in both databases with the same file to access
> these data.

Using external files doesn't work on Blobs, and converts null numerics to 0.
The last can be worked around be exporting the data that isn't null in one
batch, and then importing just the fields that aren't null when importing.

You also need to be wary of exceeding 2gig on the external files, I
purposely limit exports to 2gig (or so) just to be safe. FireBird will
happily export 3-4gigs of data to an external table, but you will not be
able to import it! Seems like it's using an unsigned 32bit file pointer on
export, and a *signed* 32-bit on import... ;-)

If you're familiar with Delphi you will find more detailed information in
the source code for IBDBRepair
which 'pumps' data from one database to another using the best possible