Hi Samuel,
I agree with Dag that this issue is a little complicated and you may
want to tackle something smaller first just to get familiar with the
Derby codeline. The objects stored in system tables, which Dag
mentioned, are a special kind of user defined type with a highly
optimized storage representation. A good place to start is to grep the
codeline for UserDefinedType. This will introduce you to a lot of
compiler support for user types.
One wrinkle of this feature is that the community will want to agree on
SQL standard syntax for declaring user types and for using them as
column and argument types. You will want to take a look at part 2 of the
2003 SQL standard, sections 4.7, 11.41, and 11.49--as well as part 13,
sections 4.8, 9.4, and 9.7. Other sections are probably relevant but
those would be a good start.
Regards,
-Rick
Dag H. Wanvik wrote:
Samuel Morgan <[EMAIL PROTECTED]> writes:
Thanks Guys,
I will register and see what I can do.. Id love to help or even start
developing it.. Im afraid I dont know where to start. Any suggestions?
Great!
For general information, have a look at:
http://db.apache.org/derby/derby_comm.html
http://wiki.apache.org/db-derby/ForNewDevelopers
As for this particular issue, maybe Rick can offer some advice?
Looking at how this is used internally in the system tables is
probably a good start, e.g. in SYS.SYSCONGLOMERATES the column
DESCRIPTOR has the type org.apache.derby.catalog.IndexDescriptor.
http://db.apache.org/derby/docs/dev/ref/rrefsistabs38369.html
It may be advisable to tackle some smaller issue first, so you know
your way around a bit before you try to attack this issue. Your call :)
Thanks,
Dag
Sam
Dag H. Wanvik wrote:
Rick Hillegas <[EMAIL PROTECTED]> writes:
Samuel Morgan wrote:
Right now you can't declare custom types in Derby. This feature has
been requested before and is tracked by DERBY-651. So far no-one has
volunteered to work on this issue.
You can vote for it, or even better, help us develop it :)
http://issues.apache.org/jira/secure/ViewVoters!default.jspa?id=12325061
Thanks,
Dag
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