Question

I am missing the methods

• compoundIndexes
• setCompoundIndexes

in NSEntityDescription in the Mac OS X 10.7 SDK. It is however, available in the iOS5.0 SDK.

Xcode on the other hand knows very well about compound indexes, even under Mac OS X. It creates xcdatamodels like this:

<entity name="OHLCV" parentEntity="Sample" syncable="YES">
    <attribute name="close" attributeType="Double" defaultValueString="0.0" syncable="YES"/>
    <attribute name="high" attributeType="Double" defaultValueString="0.0" syncable="YES"/>
    <attribute name="low" attributeType="Double" defaultValueString="0.0" syncable="YES"/>
    <attribute name="open" attributeType="Double" defaultValueString="0.0" syncable="YES"/>
    <attribute name="volume" attributeType="Integer 64" defaultValueString="0" syncable="YES"/>
    <compoundIndexes>
        <compoundIndex>
            <index value="open"/>
            <index value="close"/>
        </compoundIndex>
    </compoundIndexes>
</entity>

Can it be that Apple just forgot to include declarations of the methods in the Mac API?

Here are the docs:

Mac: http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/CoreDataFramework/Classes/NSEntityDescription_Class/NSEntityDescription.html (here the section for managing compound indexes is missing)

iOS: http://developer.apple.com/library/ios/#documentation/Cocoa/Reference/CoreDataFramework/Classes/NSEntityDescription_Class/NSEntityDescription.html

Answer 1

I have managed to call the undeclared method by declaring it myself (needs to be declared so that the compiler accepts it):

@interface NSEntityDescription ()
- (void)setCompoundIndexes:(NSArray*)anArray;
@end

later in my code, where I create my NSManagedObjectModel programmatically I can call it:

[entity setCompoundIndexes:
    [NSArray arrayWithObjects:[NSArray arrayWithObjects:@"open", @"close", nil], nil]
];

I think Apple has just forgotten to put the methods into the CoreData API. The feature is definitely available also on Mac OS X, otherwise Xcode would not offer a UI in the xcdatamodel modelling tool.

I can further confirm that the above statements are working, because I found the corresponding compound index created by CoreData in the sqlite3 database:

CREATE INDEX ZOHLCV_ZOPEN_ZCLOSE ON ZOHLV (ZOPEN, ZCLOSE);