Creat a disk File?

Where is the data? If it's in an NSString or NSData object, then those classes contain routines to write the data to a file.

If the data isn't in an Objective-C class, then I would probably end up writing the data using normal C stdio routines.

 

Break the problem down.

First, get the data out of the sql database.

If it's in C string form, then you already have it in a form you can used fprintf() on.

If the data isn't in C strings, what form is it in? Simple C types like int or float? You can still use fprintf().

If the data is in NSString or NSNumber form, then look at those classes and find methods that convert to C strings (for NSString) or simple C types (for NSNumber). Then you can use fprintf().

SInce Objective-C is a superset of plain ordinary C, you can use every C function the same way. If you already know C's stdio functions, then save yourself the trouble and just use what you know.