At 03:01 AM 24/08/2010, you wrote:

>>
>> Yes: indices are not stored in a backup.
>>
>Thank you for your answer.
>
>Finaly, updating the collation of several fields using a query then after it, doing a backup/restore, is it ok or not?

Since you "changed" the collation of the data by updating the system table RDB$RELATION_FIELDS directly, without understanding or updating related system tables, then I would expect it to have traps. For example, do you know why RDB$COLLATION_ID exists in both RDB$RELATION_FIELDS and RDB$FIELDS? Do you know what RDB$FIELD_DIMENSIONS is for? Do you know the order in which the bona fide DDL operations update the system tables or what triggers are fired from which tables? I don't: I rely on the engine to know and do the right thing.

So - what you are doing is not something I would ever recommend to do on a database I cared about. There are *good reasons* why there is a taboo on messing about with metadata directly...so good, that in FB3 you won't even be able to do it.

Just my $0.02 worth.

./heLen