Iphone Sqlite Nsdate Bug

i use core data in my iphone app, but in some case i use sqlite to access to data and ia have a problem with NSDate. NSDate *now = [NSDate date]; NSCalendar *calender = [NS

Solution 1:

In some cases you'll need to add 31 years to the dates in the SQLite DB.

From the book: IPhone Forensics: Recovering Evidence, Personal Data, and Corporate Assets By Jonathan Zdziarski On calendar events:

Unlike most timestamps used on the iPhone, which are standard Unix time-stamps, the timestamp used here is an RFC 822 timestamp representing the date offset to 1977. To convert this date, determine the actual RFC 822 time-stamp and add 31 years.

Solution 2:

For doing any query or other SQLLite operation, you should always (always!!!) use bind variables. So the query would look like:

zdate > ?

Then you make a prepared statement, bind the date variable, and execute the statement to get your results.

Solution 3:

I haven't checked this, but off the top of my head I'd guess that sqlite expects a different date format. Consider using an NSDateFormatter to convert it to the one sqlite uses.

Solution 4:

Wrong usage of NSDate in predicate!

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"date > %@",yearAgo]; - worng

I must use this:

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"date > '%f'",[yearAgo timeIntervalSinceReferenceDate];

And all works.