Zip Code to City/State and vice-versa in a database?

Question

I\'m new to SQL and relational databases and I have what I would imagine is a common problem.

I\'m making a website and when each user submits a post they have to pr

Answer 1

My understanding is that the USPS web API is free to use, but requires permission that depends on a number of factors, including the nature of the program that will be using it and the reason you need the data.

If you qualify to use it, this would presumably be the most accurate source for the information you need.