How does the iPhone SDK Core Data system store date types to sqlite?
- by Andrew Arrow
I used core data to do this:
NSManagedObjectContext *m = [self managedObjectContext];
Foo *f = (Foo *)[NSEntityDescription insertNewObjectForEntityForName:@"Foo"
inManagedObjectContext:m];
f.created_at = [NSDate date];
[m insertObject:f];
NSError *error;
[m save:&error];
Where the created_at field is defined as type "Date" in the xcdatamodel.
When I export the sql from the sqlite database it created, created_at is defined as type "timestamp" and the values look like:
290902422.72624
Nine digits before the . and then some fraction.
What is this format? It's not epoch time and it's not julianday format.
Epoch would be:
1269280338.81213
julianday would be:
2455278.236746875 (notice only 7 digits before the . not 9 like I have)
How can I convert a number like 290902422.72624 to epoch time? Thanks!
