--- In firebird-support@yahoogroups.com, Paul Vinkenoog <paul@...> wrote:

>
> Ricardo Uzcategui wrote:
>
> > i remember when you put more that 255 ddl changes in any firebird database,
> > this file can be corrupted. the solution is backup and restore before make
> > up to 255 ddl changes.
>
> IIRC, nothing gets corrupted, but once the counter is at 255 for a certain
> table, you can't commit any *additional* metadata changes *on that table*.
> A backup-restore cycle resets the counter to 0.
>
> Notice that this counter is not database-wide, but per table (and possibly
> also other objects, I'm too lazy to look that up now).
>
> Also notice that the table keeps functioning fine even with the counter
> at 255. You can enter, modify and delete data to your heart's content.
> You just can't change the metadata (the table structure) unless you back
> up and restore first.
>
>
> Paul Vinkenoog
>

The problem is when creating a database from a script. When extracting metadata and creating a database from the metadata, i think that is impossible to reach the 255 table changes. As i have read in the tracker is a known issue with 2.5.