cc = load 'countrycodes.txt' using PigStorage(',') as (ccode:chararray, cname:chararray);
 ccity = load 'worldcitiespop.txt' using PigStorage(',') as (ccode:chararray, cityName:chararray, cityFullName:chararray, region:int, population:long, lat:double, long:double);
 
 unionCountryCity = union cc, ccity;
 unionOnSchemaCountryCity = union onschema cc, ccity;
 describe unionCountryCity;
 describe unionOnSchemaCountryCity;
 
 
