QueryKit, a simple CoreData query language.
Person.queryset(context).filter(Person.name == "Kyle").delete()To retrieve objects from CoreData with QueryKit, you can construct a QuerySet for your model in a managed object context.
A queryset is an immutable object, any operation will return a new queryset instead of modifying the queryset.
var queryset = Person.queryset(context)You can filter a queryset using the filter and exclude methods, which
accept a predicate and return a new queryset.
queryset.filter(NSPredicate(format:"name == %@", "Kyle"))
queryset.filter(Person.name == "Kyle")
queryset.exclude(Person.age < 21)
queryset.exclude(Person.isEmployed)You can order a queryset's results by using the orderBy method which accepts
a collection of sort descriptors:
queryset.orderBy(NSSortDescriptor(key: "name", ascending: true))
queryset.orderBy(Person.name.ascending)
queryset.orderBy([Person.name.ascending, Person.age.descending])You can use slicing to limit a queryset to a range. For example, to get the first 5 items:
queryset[0..5]var kyle = queryset.filter(Person.name == "Kyle").get()var orta = queryset[3]queryset.count()for person in queryset {
println(person.name)
}queryset.array()This method immediately deletes the objects in your queryset and returns a count and an error if the operation failed.
queryset.delete()The Attribute is a generic structure for creating predicates providing
type-safety.
let name = Attribute<String>("name")
let age = Attribute<Int>("age")
name == "Kyle"
name << ["Kyle", "Katie"]
age == 27
age >= 25
age << (22...30)| Comparison | Meaning |
|---|---|
| == | x equals y |
| != | x is not equal to y |
| < | x is less than y |
| <= | x is less than or equal to y |
| > | x is more than y |
| >= | x is more than or equal to y |
| ~= | x is like y |
| ~= | x is like y |
| << | x IN y, where y is an array |
| << | x BETWEEN y, where y is a range |
We've extended NSPredicate to add support for the !, && and || operators
for joining predicates together.
NSPredicate(format:"name == Kyle") || NSPredicate(format:"name == Katie")
NSPredicate(format:"age >= 21") && !NSPredicate(format:"name == Kyle")Person.name == "Kyle" || Person.name == "Katie"
Person.age >= 21 || Person.name != "Kyle"QueryKit is released under the BSD license. See LICENSE.