Martijn Tonies wrote:

> When it's slow and has grown a bit largish, can you post the
> transaction counter statistics?
>
> You can get them with the command line tool "gstat" or pretty
> much any GUI tool.
>
> Martijn Tonies
> Database Workbench - tool for InterBase, Firebird, MySQL, Oracle & MS SQL
> Server
> Upscene Productions
> http://www.upscene.com
> Database development questions? Check the forum!
> http://www.databasedevelopmentforum.com
>
>

Martijn, Thanks.

You've hit the problem.
All that slowiness was due to the indexes.

In Sp now I add:
delete from tabella_rsl where mycode > 0;
execute statement 'set generator gen_tabella_rsl_id to 0';
-- aggiorna gli indici
execute statement 'SET STATISTICS INDEX TABELLA_RSL_IDX1';
execute statement 'SET STATISTICS INDEX TABELLA_RSL_IDX2';
execute statement 'SET STATISTICS INDEX TABELLA_RSL_IDX3';
execute statement 'SET STATISTICS INDEX TABELLA_RSL_IDX4';
execute statement 'SET STATISTICS INDEX TABELLA_RSL_IDX5';
execute statement 'SET STATISTICS INDEX TABELLA_RSL_IDX6';
execute statement 'SET STATISTICS INDEX TABELLA_RSL_IDX7';
execute statement 'SET STATISTICS INDEX TABELLA_RSL_IDX8';

All works fine.

Thanks a lot.

Arn