jsolderitsch wrote:
I got lots of good help with my last query.
I am trying to access a MonetDB through Sun's Glassfish app server.
I am following an example that uses the Java Persistence API and Netbeans 6.0 beta 2 that has some interesting automation to generate code, in particular for configuration file generation that define the jndi context.
But my example doesn't work. My code is based on a tutorial I found that uses Derby which is built into Glassfish.
I see the errors:
TopLink, version: Oracle TopLink Essentials - 2.0 (Build b58g-fcs (09/07/2007)) Server: unknown RAR5038:Unexpected exception while creating resource RAR5117 : Failed to obtain/create connection from connection pool [ jdbc_monetdb_localhost_demoPool ]. Reason : Connection could not be allocated because: Unable to connect (localhost:45123): Connection refused RAR5114 : Error allocating connection : [Error in allocating a connection. Cause: Connection could not be allocated because: Unable to connect (localhost:45123): Connection refused] Internal Exception: java.sql.SQLException: Error in allocating a connection. Cause: Connection could not be allocated because: Unable to connect (localhost:45123): Connection refused Error Code: 0 Local Exception Stack: Exception [TOPLINK-4002] (Oracle TopLink Essentials - 2.0 (Build b58g-fcs (09/07/2007))): oracle.toplink.essentials.exceptions.DatabaseException Internal Exception: java.sql.SQLException: Error in allocating a connection. Cause: Connection could not be allocated because: Unable to connect (localhost:45123): Connection refused
I looked at the class MonetDataSource in the JDBC jar file and I see that the constructor for MonetDataSource uses 45123 for the field portNumber. But there is no apparent way to set the portNumber to something else.
How do I get MonetDB to listen on this port? It seems that the default port is 50000. Is there a conf setting I can make to get this to work?
What is the difference between portNumber here and port value as checked for in the Driver class?
Any help appreciated.
Jim
I dug into this a little and it seems that if I change the mapi_port to 45123 in the .conf file and then use the port number explicitly in my JDBC connection URL string I can indeed use MonetDB in the same style as I saw in the tutorial. My glassfish example now works. If I leave the mapi_port set as 0, the default port number is used and with JDBC, I did not need to use the port number when I did simple queries from inside netbeans.
A side effect is that I need to use a -p option when I use mclient from the command line.
Maybe if in my JDBC url, I explicitly used port 50000, could leave the default setting alone? I will try this.
Another difficulty was I used a column name (missionNumber) that seemed to cause the code generation for the JPA classes to produce weird effects. I found that I could not use the query:
select missionNumber from missionstatus
as SQL. I found I needed to use:
select "missionNumber" from missionstatus
I changed the column name to mission_status and then the generated Java names were as expected.
And I could use the query:
select mission_number from missionstatus
without the quotes.