Predicate NSFetchRequest

Question

I have a SQLite-enabled data warehouse and want to get a list of managed objects with NSFetchRequest. I want the specified list to be sorted by a boolean value that can be easily calculated at the database level. I know this because the same conditions can be formulated using NSPredicatewhich would look like this:

[NSPredicate predicateWithFormat:@"uid = %@", currentUID]

Unfortunately, it seems that there is no way to formulate such a condition using NSSortDescriptor. How am I best to do this? Do I get two lists, one with

[NSPredicate predicateWithFormat:@"uid = %@", currentUID]

and one with

[NSPredicate predicateWithFormat:@"uid != %@", currentUID]

and combine them later? Can I still use it elegantly NSFetchedResultsController?
Or should I get all the elements and sort them later in the code? Or I didn’t miss anything.

Answer 1

Just create an array (even if it contains only one element) NSSortDescriptorsto sort the result as desired.

You use setSortDescriptors:to install them.

An extract can simultaneously process both predicates and sort.

Answer 2

What you are asking for does not make sense.

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