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# toManyRelationshipKeys

Overridden by subclasses to return the keys for the to-many relationship properties of instances of the described class.

```
var toManyRelationshipKeys: [String] { get }
```

## Return Value

An array of `NSString` objects containing the names of the to-many relationship properties of instances of the described class.

## Discussion

To-many relationship properties are arrays of objects.

If you have an instance of the class the receiver describes, you can use the `NSObject` instance method <doc://com.apple.documentation/documentation/ObjectiveC/NSObject-swift.class/toManyRelationshipKeys> instead.

## See Also

[`attributeKeys`](/documentation/Foundation/NSClassDescription/attributeKeys)

Overridden by subclasses to return the names of attributes of instances of the described class.


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