How to split mobile number into country code, area code and local number? e.g +919567123456 after split
country code = 91
area code = 9567
local numb
The answer very much depends on the country. There is no universal rule saying "this is country code, this is area code, this is local number". The only information that can be gained universally is the country number (and even that can be 1-4 digits long); then you need to consult the specific country's ruleset.
For examples (like, "there are many different phone numbers in the given countries, but they all follow the same format"):
If you strive accurate UK data see also http://code.google.com/p/ofcom-csverter/ for a complete list of UK area codes with corrections.
It's not possible to parse phone numbers with a simple algorithm, you need to use data tables populated with each country's rules - because each country delimits their phone numbers differently.
The country code is fairly easy, just use the data from from the Country calling codes article in wikipedia and build a table of all the unique country codes. Each country has a unique prefix, so that's easy.
But then you need to look up the rules for every country you want to support and extract the area code(s) using the rules for each country.
A very complex problem. First you need to determine the country code. Depending on the country code, the rest has to be splitted into area code and local number. But none of the three parts has a fixed length, not the hole number nor the area code and local part combination!
Example: 4930123456789
Example: 493328123456
Example: 34971123456
As mentioned by various people you can not do this with simple string matching. The lengths of neither country nor area codes are fixed.
Having done this in the past we maintained a table similar in structure to the following :-
+------------+---------+-------+--------------+ |country_code|area_code|country|area | +------------+---------+-------+--------------+ |44 |1634 |UK |Medway | |44 |20 |UK |London | |964 |23 |Iraq |Wasit (Al Kut)| |964 |2412 |Iraq |Unreal | +------------+---------+-------+--------------+
We then calculated the maximum length of area_code and country_code and checked the string by sub-stringing starting at the maximum length and working our way down until we found a match.
So given the number 441634666788
We would have started at the substring[1,7] (7 being the length of the longest country/area code combination), not found a match, then moved on to [1,6] and found the match for UK/Medway.
Not very efficient but it worked.
EDIT
You could also try something like this but you would need to test it with a full data set or maybe even break it down into separate country and area code selects as it may not be very performant with your chosen DB.
DECLARE @area_codes TABLE
(
country_code VARCHAR(10),
area_code VARCHAR(10),
country VARCHAR(20),
area VARCHAR(20),
match_string VARCHAR(MAX),
match_length INTEGER
)
INSERT INTO @area_codes VALUES ('44','1382','UK','Dundee', '441382%', 6)
INSERT INTO @area_codes VALUES ('44','1386','UK','Evesham', '441386%', 6)
INSERT INTO @area_codes VALUES ('44', '1', 'UK', 'Geographic numbers', '441%', 3)
DECLARE @number VARCHAR(MAX)
SET @number = '441386111111'
SELECT TOP 1 *
FROM @area_codes
WHERE @number LIKE match_string
ORDER BY match_length DESC
You would maintain the match_string and match_length fields through a trigger, taking care to cope with null area codes and index the table on the match_string column.
I think you will need something like a dictonary of country and area codes. because booth of them can have a different lenght. USA +1, Germany +49, even +6723. Same with the Areacodes..