New function which returns the formatted left join query. This is required as Oracle and postgres have different left join syntax
Add method as parent class adding a method.
Get rid of toDate method. It inherentise from AbstractAdaptor.
Add new method to handle toDate function.
Change back to pass connection as a parameter. Because new connection will cause an error.
Using getDBConnection method rather than a parameter.
rename the DB* classes to:AbstractDatabaseOracleAdapterPostgresqlAdapterSqlserverAdapter