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derby数据库源码。。。。。。。。。。。。。

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This directory tree contains a demo application which shows how you
can run user-written Java code inside the Derby database. 

For instructions on how to build and run the demo application, cd to this
directory and type the following command:

   ant -projecthelp

The demo shows you how to do the following:

o Declare Java functions and procedures and run them inside the Derby
   engine.

o Load the Derby engine with jar files of user-written code.

o Enforce data consistency by wiring functions into CREATE TABLE
   statements.

o Run a Java procedure from a TRIGGER.

o Improve query performance by wiring filtering functions into the
   WHERE clause.

o Format query output by wiring functions into the SELECT list.

o Re-use off-the-shelf packages to write your own custom data aggregator.

For more detail, please consult the following sections of the Derby
Developer's Guide:

o "Loading classes from a database"

o "Derby server-side programming"