Dear Adrian, thank you for the reply! >> i am struggling with a problem due, sometime, to a double concurrent update on the same row of a table. >What is the error message you get? We have no error, but the two queries, in "Lock wait", keep stucked for some minutes before completed. Are there any parameters useful to "serialize" in some way two different Update queries - for the same field in the same row - arriving concurrently? I was looking at the lock_timeout parameter: could it be what i am looking for? Thank you! Franco