Hi Hallvard, I want to thank you so much for your timely responses. I'm very glad to interact with a so responsible team. Changing MDB_CREATE is clearer, indeed allows separate both sets with a simple mask. Talking about the documentation, I think that should be stressed somewhere that when using named databases, the main one (unnamed) should not be used for regular work without special care and some constraints. Maybe that a remark in mdb_dbi_open would be sufficient. Regards and thanks again. Salvador. On 08/14/2013 02:06 AM, Hallvard B Furuseth wrote: