>Recently i droped 4 tables and created 4 views with the same name. Is
>it possible that this error is related to this change?

Did you do this whilst others were connected to the database? Not all too long ago (I wrote the message "Fb 1.5.4 - RDB$RELATION_FIELDS not in RDB$RELATIONS" and sent it to this list 23 July, but searching yahoogroups doesn't seem to find messages from July and August), we dropped and recreated a stored procedure and a table because we wanted to change some names. This procedure and table weren't used by anyone at the time (they were new, and not yet used in any program), so we thought it would be safe to do this. The result was that we got fields referred to in some system tables (at least RDB$RELATION_FIELDS and RDB$RELATION_CONSTRAINTS) belonging to tables no longer existing in RDB$RELATIONS. The error was only discovered since DB Workbench complained heavily. This list couldn't help in explaining what had happened, and we decided (after shutting down the database and making sure that we had both a backup and a file copy in case things went wrong) to try simply removing these stray field references from the system tables. We've not yet discovered any problems after doing this, so I believe we were lucky.

Your problem seems different, but it may be a similar cause. Have you checked that the rdb$relation_id's in question aren't referred to in other system tables than rdb$relations? If you find that they are, I don't know Firebird well enough to dare recommend deleting the records from the system tables...

I think we're going to be more careful and avoid deleting tables (at least tables with indexes or keys) whilst others are doing any DML to the database, even if the table we're deleting isn't in use.

HTH,
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