Metacat

rename the DB* classes to:
AbstractDatabase
OracleAdapter
PostgresqlAdapter
SqlserverAdapter

included new function that returns db specific non-null function name

- new db adapter for MS SQL Server
- changed the getUniqueID(conn, tableName) to return the last generated by the db unique ID
instead of generating unique ID first by the appl and then supplied to the insert,
because SQL Server doesn't have capabilities
unique ID to be generated on the client and then supplied to the insert.

changed the getDate method to getDateTime and changed the return
string in the postgresql implementation to "now()" from now()::date

change the method name getDateString() to getDateFunction()
return "now()::date" in the DBPostgresql implementation of that method

The Postgres implementation of the dbadapter package, still needs testing and
the getDate... method just returns the db function to return the date; to retreive the
current time is a second function so we may want to add a second method to return the
current time.

the abstract DBAdapter class and its Oracle implementation
for the new dbadapter package