Creating EPSG database for HSQL

The following instructions are for module maintainers. They explain how to update the epsg-hsql plugin with latest EPSG database. Users don't need to read this page - the epsg-hsql plugin should work "out of the box" without any particular action required.

The following gives some hints for creating a HSQL database and populate it with EPSG data from the SQL scripts.

Copy the sqltool.rc file in the developper's home directory and edit it URL path provided in this file.
Prepare a copy of EPSG's SQL scripts and modify them for HSQL syntax. The following Ant file can be used for this purpose. As a safety, add the following lines at the end of every scripts:
```
COMMIT;
SHUTDOWN;
```

Creates the database using the following commands:

java org.hsqldb.util.SqlTool --autoCommit EPSG-admin HSQL/EPSG_Tables.sql
java org.hsqldb.util.SqlTool --autoCommit EPSG-admin HSQL/EPSG_Data.sql
java org.hsqldb.util.SqlTool --autoCommit EPSG-admin HSQL/EPSG_FKeys.sql

Launch the following application:

java org.hsqldb.util.DatabaseManagerSwing

Make sure the database is okay, and invoke the following commands:

SCRIPT 'EPSG.sql';
SHUTDOWN COMPACT;

Quit the application. Edit the EPSG.sql script as below:
- Remove the SET DELAY 60 statement; 60 is already the default.
- Remove the CREATE USER "SA" and GRANT DBA TO SA statements. This user will exists before the script is run.
- Remove the CREATE SCHEMA PUBLIC and SET SCHEMA PUBLIC statements. This schema will exists before the script is run.
- In the table EPSG_DATUM, change the type of column REALIZATION_EPOCH to INTEGER.
- Copy all ALTER TABLE ... FOREIGN KEY statements to the end of the script.
- Remove all CONSTRAINT ... FOREIGN KEY from the CREATE TABLE statements at the begining of the script, and move them as ALTER TABLE ... FOREIGN KEY statements at the end of the script.
- Add SHUTDOWN COMPACT statement at the end of file.

Run the following commands:

java org.geotools.referencing.factory.epsg.Compactor

Copy the file created in the above step into the org.geotools.referencing.factory.epsg package directory using "EPSG.sql" filename. Finally, create the JAR file as usual, which should includes the EPSG.sql script.