Oh!DB Table Data Gateway

This class implements the Martin Fowler TDG (Table Data Gateway) pattern using the ADODB library.

- Execute SQL SELECT queries from list of fields of a table
- Retrieve the highest or the lowest value from an integer primary key table field
- Get or delete one record of a table with a given primary key value
- Delete all records of a table
- Delete a record from a table and references from other tables
- Start and end transactions
- Etc..