Creating a Java named query?

Question

Hi,
From the application developers manual; is it implied that named queries can be created using the Oracle Toplink API in Java; i.e out of the workbench but I have not been able to find any references to this elsewhere. Does anyone have any information on this? i.e creating the named query in Java code and then adding it to the project deployment.
In addition, is it possible to have it such that if a named query expects 4 arguments; the Java code is written to check if there are any null values passed in, and if the values are null those columns wlil be removed from the query.

Answer 1

There are really two types of queries that apply.
Named queries being those queries defined in Java code at application start up that take a fixed number and types of parameters. These queries are typically added using descriptor after-load methods. In the MW you select the static after-load method where you wish to define your queries. As of TopLink 9.0.4 it is possible to define your named queries with arguments directly in the MW without an after-load method.
Redirect queries are queries where TopLink invokes your method at runtime to execute the query. This approach allows for your code to selectively build the where clause based upon the arguments passed in.
Some links into the docs that may be of interest:
after-load: http://download-west.oracle.com/docs/cd/B10464_01/web.904/b10316/dscriptr.htm#1014978
Using named queries: http://download-west.oracle.com/docs/cd/B10464_01/web.904/b10313/queries.htm#1146839
Redirect queries: http://download-west.oracle.com/docs/cd/B10464_01/web.904/b10313/queries.htm#1141580
Doug