Using Predicate Builder for creating a search criterion
Xcode provides a visual tool: Predicate Builder that helps in creating predicates (queries for extracting rows from entities) for us. Let us try using the Predicate builder to display all customer names that contain characters 'Ca'
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So, let us open our Data Model by double-clicking the prob.xcdatamodel file in the Resources group in the Xcode Project window. Xcode's data modeling tool will open and we find our Customer entity in it. From the Property pane, select the + (plus) button, a menu with several options such as: Add Attribute, Add Fetched Property, Add Relationship, and Add Fetch Request will popup. Out of these four options, Add Fetched Property and Add Fetch Request can be used for building predicates. Let us see them one by one.
Fetched properties
A fetched property is a type of attribute that associates a managed object with other managed objects based on the specified condition. That is, the predicate to define the objects...