Class FB: Wrapper to access Firebird databases

This class is a wrapper to access Firebird databases.

It can:

- Establish database connections
- Execute simple queries
- Execute SELECT queries restrict the range of rows that a query returns to perform pagination
- Retrieve query result rows as arrays
- Retrieve query result BLOB field values
- Manage transactions
- Verify the syntax of n INSERT query to determine whether it is valid
- Check if a table or a table field exists
- Retrieve the next sequence value associated to table
- Retrieve the time and date of the database server

The code and the comments are in Portuguese.