1. Senior Staff Engineer, Sun Microsystems
Saur
Saucer Separation
Rick Hillegas
Senior Staff Engineer, Sun Microsystems

2. Derby-style table functions to be introduced in Derby 10.4
Use SQL on non-relational data
Tear-off subsets of other databases

3. Overview of Table Functions
Log Files
XML Reports
External DBMSes
Snapshots

4. O Overview of Table Functions Implementing a Table Function Demo Code
Creating a Table Function
Invoking a Table Function
Optimizing a Table Function O

5. Implementing a Table Function
Implement java.sql.ResultSet – extend a demo class if appropriate
Stub out all methods except:
next()
close()
getXXX() -- for the datatypes of your columns
Create a public static method which returns your implementation of java.sql.ResultSet

6. Demo code in java/demo/vtis...
Table Function for rows of String columns
Table Function wrapping a text file
Table Function wrapping a properties file
Table Function wrapping an xml file
Table Function wrapping external query
Subscription to foreign SQL data

7. Creating a Table Function

8. Invoking a Table Function

9. Optimizing a Table Function
Advanced topic
Class containing Table Function must have a 0-arg constructor
It must implement org.apache.derby.vti.VTICosting

10. Log Files
Plain text log files
XML log files

11. Plain text log files
Have regular structure
Sequence of records (rows)
Each record has fields (columns)
SQL is a great tool for mining these records

12. XML Log Files
Again, regular structure
Repeating elements (rows)
With attributes/sub-elements (columns)
SQL is a great tool for mining these files

13. Reports
Exported in XML
Easy to mine using SQL and Table Functions

14. External DBMSes
Foreign DBMS Data
Migrating Foreign Data into Derby

15. Foreign DBMS data
Use Table Functions to import data from foreign databases
Demo classes make it easy to create a Table Function which runs a query against a foreign database

16. Migrate foreign data into Derby
Use Demo classes to create Table Function which runs a foreign query
Use 'create table ... as select' to create Derby table from Table Function shape
Use 'insert into ... select * from' to pipe data from foreign database into Derby

17. Snapshots
Use Demo classes to declare a parameterized subscription to foreign data
Use Demo procedures to plug in new parameters and tear-off a fresh copy of the subscription