Is there a database with location -> name of timezone as per IANA Time Zone Database [closed]

Question

In my script (PHP), I use the tz database label for each location in my database: http://en.wikipedia.org/wiki/Tz_database

I am entering a whole series of places (countries, provinces, states, cities, etc.) from around the world, and for each, I have found it very difficult to know which label from the IANA Time Zone Database to use.

Searching the location on wikipedia gives me the time offset (UTC+n) and the timezone abbreviation (EST, etc.) but neither helps in knowing which entry to use in the tz database.

E.g.: Washington DC uses, as best as I could figure out, 'America/New_york'.
Dallas, TX uses 'America/Chicago' (unless I'm mistaken!)

There is a small African country for which neither its capital city nor its largest city were in the tz database. Which tz entry to use?

There must be a database somewhere, or a resource which clearly links every location on earth (country, state, province, city, etc.) to a specific entry in the tz database. Where can I find it?

Answer 1

combining google map API works fine for example use below API to get location from address. address is "Mountain View, CA, US"

https://maps.googleapis.com/maps/api/geocode/json?address=Mountain+View,+CA,+US&key=YOUR_API_KEY

this URL returns JSON some thing like this

{
   "results" : [
      {
         "address_components" : [
            {
               "long_name" : "Mountain View",
               "short_name" : "Mountain View",
               "types" : [ "locality", "political" ]
            },
            {
               "long_name" : "Santa Clara County",
               "short_name" : "Santa Clara County",
               "types" : [ "administrative_area_level_2", "political" ]
            },
            {
               "long_name" : "California",
               "short_name" : "CA",
               "types" : [ "administrative_area_level_1", "political" ]
            },
            {
               "long_name" : "United States",
               "short_name" : "US",
               "types" : [ "country", "political" ]
            },
            {
               "long_name" : "94043",
               "short_name" : "94043",
               "types" : [ "postal_code" ]
            }
         ],
         "formatted_address" : "Mountain View, CA 94043, USA",
         "geometry" : {
            "location" : {
               "lat" : 37.4224764,
               "lng" : -122.0842499
            },
            "location_type" : "GEOMETRIC_CENTER",
            "viewport" : {
               "northeast" : {
                  "lat" : 37.4238253802915,
                  "lng" : -122.0829009197085
               },
               "southwest" : {
                  "lat" : 37.4211274197085,
                  "lng" : -122.0855988802915
               }
            }
         },
         "place_id" : "ChIJ2eUgeAK6j4ARbn5u_wAGqWA",
         "types" : [ "street_address" ]
      }
   ],
   "status" : "OK"
}

and you can extract location from JSON and call location to time zone API.

API call sample:

 https://maps.googleapis.com/maps/api/timezone/json?location=39.6034810,-119.6822510&timestamp=1331161200&key=YOUR_API_KEY

that returns JSON like this

{
   "dstOffset" : 0,
   "rawOffset" : -28800,
   "status" : "OK",
   "timeZoneId" : "America/Los_Angeles",
   "timeZoneName" : "Pacific Standard Time"
}