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How do you perform address validation?
I have a requirement to validate and then correct data consisting of street address, city, state and country.
Is there a way to use Google-map APIs/functions to do this? Ie. input the dubious address fields and output the correct ones?
It would also be great if the function could output the geographic coordinates of the address.
State, prolly. City ... hmmm. See steeet ... depends how liberal Google is with contractions ... Dr=drive, St=street, but also Saint ... #1 St. Guiness S, St. Paul, Mi ....
Suck it and see ... my guess? No, not with certitude.
But, why ask us? Why not ask Google? Or http://www.openstreetmap.org/
An address is a physical location on the planet. In order to have a fully validated address, everything has to be correct. You have to have a house number that actually exists on the right street. You have to have a street that is spelled correctly and actually exists in the right city. You have to have a city that exists in the state and then you have to have a state that exists in the country. What you need is a way to compare your address against a master address list. You need some sort of address verification.
Most countries do not have a reliable master address list. The number of countries with accurate list is small but growing. Here are a few: USA, Canada, England, Germany. Certainly there are more but the majority of countries DO NOT.
Google maps does not actually validate an address. They will let you know that an address fits within a certain range of house numbers. For example, for any city block, the starting and ending primary number range can be determined. If an city block has 10 houses on it and each house number goes up by 50, then you would have house numbers like this, 50, 100, 150, 200… However, on google maps, you could also enter an address of 32 on that same street and it would map it for you. If you take the time to look at StreetView (if it exists) you would see that the number 32 is halfway between two different houses and probably doesn't really exist. That is not a fast way to do it nor is it a very highly accurate way.
In other words, Google Maps is like doing a checksum on a credit card number. We can see that the credit card might be good because it passes some basic tests, but to see if a credit card is actually good, it needs to be submitted for an authorize transaction. And if your system was collecting credit card information (or street info in this case), wouldn't it be nice to know if the data collected is real instead of potentially real?
There are a number of address verification services that do have API access. Using one of these you would be able to determine if an address is real and deliverable. In the US, this data is updated monthly by the US Postal Service.
I am the founder of SmartyStreets, we provide address verification for addresses within the United States.
