#90 failure to close connections

closed
Heiko Hilbert
None
5
2011-10-19
2011-10-19
eugene
No

I tested several times - With Eclipse+sqlexplorer plugin I connect to JavaDB using embedded driver (from JDK 1.6.27) using derby.jar (new profile had to be created). Once connected I disconnect. That works fine. I go to SQLExplorer app (with eclipse built in) and try to connect but I get exception saying that there is someone else already connected. However, if I close the eclipse+plugin I can connect with SQLExplorer app. That means the connection was not released until I closed eclipse+plugin

Note that JavaDB embedded allows only one connection to DB.

Discussion

  • eugene
    eugene
    2011-10-19

    Same happens if I use SQL Explorer and Eclipse DTP. Closing connections does not release resources and the other app cannot connect until I actually shut down the whole app.

     
  • Heiko Hilbert
    Heiko Hilbert
    2011-10-19

    That is not a bug.
    It is because you are using the embedded driver. Which mean you have started a 'database server' in that JVM on your data filese. So after opening one connection the 'database server' is started and will reelase the databse files only if you shutdown the embedded database or close the VM.
    Here:
    http://db.apache.org/derby/papers/DerbyTut/embedded_intro.html#shutdown
    you can find this:
    >>>>
    Derby supports multiple connections to a given database. An example of an embedded application that manages concurrent users is a Tomcat or Geronimo application server that embeds Derby. Any number of users can execute Web applications that access a database through that Web server.

    However, only one JVM may boot ("open") that database, so multiple applications running in different JVMs cannot access the same database.
    <<<<<<

    Your solution could be to use the Derby network server and network client. This is described here:
    http://db.apache.org/derby/papers/DerbyTut/ns_intro.html

    Regards
    Heiko

     
  • Heiko Hilbert
    Heiko Hilbert
    2011-10-19

    • assigned_to: nobody --> hhilbert
    • status: open --> closed