When pilots think of an airport, they think of anywhere they can safely and legally land their planes. It might or might not have a a fence, pavement, fuel pumps, or any structures at all (even an outhouse), much less a terminal building with departure gates and a security checkpoint.
When non-pilots think of an airport, they usually think of somewhere they can buy a ticket and get on a plane. Even in a small city, it will usually have an overpriced parking lot, paved runways, an ugly terminal building, fuel trucks, etc. etc.
Have it your way …
I want to make OurAirports useful for both groups of people, so I’ve been scavenging information on the web to flag which of the 33,000+ airports currently in the database have any kind of scheduled airline service (even in a light piston twin). The roughly 3,000 airports that I’ve found with airline service are now flagged in the database, and have a small note at the top of their right sidebars. Soon, I’ll make changes so that people who want to see only airports with airline service can filter out everything else.
This stuff changes all the time, and my sources might not be entirely reliable, so please send me corrections etc.
CSV format change
NB: for anyone using the CSV data export at http://www.ourairports.com/data/airports.csv, the format will be changing as of tomorrow, adding an extra column “scheduled_service” with the value “yes” or “no”. As far as I know, this is the only free, machine-readable dataset with this information available online.
Photo courtesy of Wikimedia Commons.
Land and Hold Short 
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That’s one huge csv. I’ve Wouldn’t it be easier to divide the locations up into separate files divide by continent and load them like modules? I’ve only programmed for about 5 years, but I’ve learned whenever you need to work with that much information, it’s better to divide it up into smaller data. It saves loading time (provided someone’s not trying fly to all continents at the same time), and much easier to maintain.
I’ve read your post about the airports that have no country or are in between countries, but as a workaround you could also have a extra “special-airports” file that could be loaded before everything else.