How to display a map direction which fetches latitude and longitude from sqlite database

HI all,

i have map application which stores the latitude and l开发者_开发知识库ongitude of location in sqlite database. Depending on the existing latitude and longitude saved in sqlite database,i want to display a new map.How is it possible.Can anybody help me in solving this problem.Thanks.

 NSString *urlstring=[NSString stringWithFormat:@"http://maps.google.com/?saddr=%f,%f&daddr=%f,%f",sourcelocation.latitude,sourcelocation.longitude,destinationlocation.latitude,destinationlocation.longitude];