I use the JDBC Jaybird driver for my Spring Boot application and also for DBeaver - both started having a problem loading data that has a BLOB included in it. The problem always appeared after upgrading to Firebird 4.0.3 (tested on two operations).

Error: Could not extract column [85] from JDBC ResultSet [invalid BLOB ID [SQLState:42000, ISC error code:335544329]]

I have no idea where the problem could be. This never happened to us with FB version 4.0.2 and lower (or 2.5).

Since it does this in both Spring Boot and DBeaver, I would say that the problem is somewhere in the settings or the JDBC driver itself.

The fix is if I run this on the given BLOB attribute:
UPDATE XY SET BLOB='' WHERE BLOB='';

But after a certain time, the problem recurs. During a full day of development and working with the database, this will happen at least once a day. Otherwise, the database goes through backup & restore every day without any problems.

Can't you think of what it could be?