iOS Swift Compound Predicate

I'm trying to do a search for specific items within Core Data

I have an Entity Colour, which has a NSSet of ProjectColour Entities. The ProjectColour Entities have a field called project which is a Project Entity, and two int fields called fullLeft and partialLeft. This has a field called drillType which is a string.

I'm trying to all objects that have a drillType of Square and both fullLeft and partialLeft > 0

I've tried

if searchedText.lowercased() == "square" {
    let predicateNumbers = NSPredicate(format: "ANY projectColours.fullLeft > 0 OR ANY projectColours.partialLeft > 0")
    let predicateDrillType = NSPredicate(format: "ANY projectColours.project.drillType == 'Square'")

    fetchRequest.predicate = NSCompoundPredicate(type: .and, subpredicates: [predicateNumbers, predicateDrillType])
}

This works when searching for Round as the type but with squares, its returning the wrong objects i.e. Two objects, one which is a square but partial and full are equal to 0 The second is a Round which has partial equal to 1

Example 3 Colour Objects

• 1
• 2
• 3

3 Project Colour Objects

• 1st. Colour (linked to colour) = 1, Full = 1, Partial = 1, Project (linked to project entity) - Drill Type = Square
• 2nd. Colour = 2, Full = 1, Partial = 1, Project (linked to project entity) - Drill Type = Round
• 3rd. Colour (linked to colour) = 1, Full = 0, Partial = 0, Project (linked to project entity) - Drill Type = Square

When searching, I get for square, I get all 3 results return, even through the second Project Colour object is Round

When searching for text, I want all ProjectColour.project.drillType of Square and ProjectColour.fullLeft > 0 AND ProjectColour.partialLeft > 0

fetchRequest.predicate = NSPredicate(format: "ANY projectColours.project.drillType == 'Square'") - Works

fetchRequest.predicate = NSPredicate(format: "ANY projectColours.fullLeft > 0 OR ANY projectColours.partialLeft > 0") - Works

But when I try and combine the two it doesn't work

Assuming that you want to search for all Colour objects which have some related ProjectColour object with the given project.drillType and positive fullLeft and positive partialLeft: You need a SUBQUERY for such a request. Something like (untested):

let pred = NSPredicate(format: """
    SUBQUERY(projectColours, $pc, $pc.fullLeft > 0
                                    AND $pc.partialLeft > 0
                                    AND $pc.project.drillType ==[c] %@
            ).@count > 0
""", searchedText)

Note also that keyword substitution with %@ is preferred over string literals inside the predicate format string, and that ==[c] can be used for case-insensitive string comparison (so that the search text does not need to be converted to lowercase)