I am implementing a nightly updated and formatdb script for the BLAST unformatted databases from NCBI. A researcher today asked a question that I could not answer. His question was, if he runs a long BLAST search during the time my script is running, what will happen to his returned search? Will he get false positive from both databases (the old one and the newly created one)? Will the database be locked out during his search and my script will fail? I was amazed that I didn't think of this sooner. What does everybody here use as a script and how do you prevent the database from being newly formatted if a current BLAST search is running? Thanks for any answers. -- Jeremy Mann jeremy@biochem.uthscsa.edu University of Texas Health Science Center Bioinformatics Core Facility Phone: (210) 567-2672