STD phone code lookup

Another one of those problems I don't know how to ask easily.

I need to locate the operator for a phone number.

The operator is linked to the first digits of the phone number but the number of digits varies from number to number possibly from 3 to 7 digits.

I can control the data and the lookup tables. Anyone done something like this?

I can handle things programatically in simple single record lookups but what about user generated reports.

The longest match on a number would be what we need. ie if we get a match at 5 digits then we don't need to look up 4 or 3. Record numbers are not great, about 250 000 per annum and most processing is batch/automatted but reports and status screens are updated regurly (every minute) so this may need to work quite fast. Received on Mon Feb 18 2002 - 10:16:49 CST