Nspredicate Cheat Sheet printable pdf download

NSPredicate Cheatsheet

Basic Comparisons

Presented by Realm: a mobile database that replaces

=,==

Left hand expression is equal to right hand expression

Core Data and SQLite. Learn more at

Left hand expression is greater than or equal to right

>=,=>

supported by Realm

hand expression

Left hand expression is less than or equal to right hand

<=,=<

expression

Format String Summary

Left hand expression is greater than right hand expression

Left hand expression is less than right hand expression

@"attributeName == %@"

object’s attribute name is equal to value passed in

!=,<>

Left hand expression is not equal to right hand expression

@"%K == %@"

Left hand expression must appear in collection specified by

pass a string variable to %K, it will be represented as a

right hand expression. i.e. name IN {‘Milk’, ‘Eggs’, ‘Bread’}

keypath

Left hand expression is between or equal to right hand

BETWEEN

@"%name IN $NAME_LIST"

expression. i.e. 1 Between {0, 33}

templated for predicate, checks if the value of key name is

predicateWithFormat: @"expenses BETWEEN {200, 400}"

in $NAME_LIST. Uses predicateWithSubstitutionVariables

Basic Compound Predicates

@"'name' IN $NAME_LIST"

checks if the constant value ‘name’ is in $NAME_LIST. Uses

predicateWithSubstitutionVariables

Logical AND

AND,&&

predicateWithFormat: @"title == %@", @"minecraft"

Logical OR

OR,||

Logical NOT

NOT,!

Keypath collection queries

predicateWithFormat: @"age == 40 AND price > 67"

returns the average of the objects in the

@avg

String Comparison Operators

collection as an NSNumber

returns the number of objects in a collection as

@count

Left hand expression begins with the right hand

an NSNumber

BEGINS WITH

expression

returns the minimum value of the objects in the

@min

collection as an NSNumber

Left hand expression contains the right hand

CONTAINS

expression

returns the maximum value of the objects in the

@max

collection as an NSNumber

Left hand expression ends with the right hand

returns the sum of the objects in the collection

ENDSWITH

expression

@sum

based on the property

predicateWithFormat:

Left hand expression equals the right hand

@"expenses.@avg.doubleValue < 200"

expression: ? and * are allowed as wildcard

characters, where ? matches 1 character and *

matches 0 or more characters

Subqueries

Left hand expression equals the right hand

MATCHES

expression using a regex - style comparison

SUBQUERY(collection, variableName, predicateFormat)

predicateWithFormat: @"name BEGINS WITH 'm'"

Iterates through the collection to return qualifying queries

Aggregate Operators

Collection - array or set of objects

variableName - variable that represents an iterated object

returns objects where ANY or SOME of the predicate

predicateFormat - predicate that runs using the

ANY,SOME

results are true.

variableName

returns objects where ALL of the predicate results are

ALL

predicateWithFormat: @"SUBQUERY(tasks, $task,

true.

$task.completionDate != nil AND $task.user = 'Alex')

returns objects where NONE of the predicate results

.@count > 0"

NONE

are true.

Assume this was run on an array of projects. It will return

projects with tasks that were not completed by user Alex

predicateWithFormat:@"ALL expenses > 1000"

Nspredicate Cheat Sheet

Related Articles

Related forms

Related Categories