derby:net is to connect to the network server, which could be running on another machine. it has host:port to connect to. You start the derby network server and it runs as a database server to serve many clients.
jdbc:derby:dbname is used to connect to a local database in embedded mode (derby classes run as part of your application). in this case, derby is not running as a server listening on a port number. your application is the database engine in that case. there is no host:port in such urls. URL could be like:
only 1 process at a time can use a local database using jdbc:derby:dbname connection.

Maryam Moazeni <> wrote:
What is the difference between this
"jdbc:derby:net://localhost:1527/" ??
Thanks in advance,