CoreData NSPredicate with relationship

Question

I have following CoreData objects Model

enter image description here

Now I am having issue in making a predicate with following conditions.

Fetch all those DBOpportunity WHERE

DBOpportunity.stateCode == 1

AND

DBOpportunity.invoiceDate >= GIVEN_DATE

AND

DBOpportunityLines.crmAccept == 1 OR DBOpportunityLines.crmAccept == 3

I have tried lots of examples and programming guide by the apple but can't able to achieve this.

Martin R · Accepted Answer · 2020-08-05T17:59:16.390

3

opportunitylines is a to-many relationship, so there are multiple DBOpportunityLines objects for one DBOpportunity object. Assuming that the last condition

DBOpportunityLines.crmAccept == 1 OR DBOpportunityLines.crmAccept == 3

should hold for any of the related objects, you need a SUBQUERY:

NSDate *givenDate = ...;
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"stateCode == 1 AND invoiceDate >= %@ "
    "AND SUBQUERY(opportunitylines, $x, $x.crmAccept == 1 OR $x.crmAccept == 3).@count > 0",
    givenDate];

Remark: Unfortunately, the usage of SUBQUERY in predicates is poorly documented. There is one example in the NSExpression class reference. See also Quick Explanation of SUBQUERY in NSPredicate Expression.

edited Aug 05 '20 at 17:59

answered May 24 '13 at 06:58

Martin R

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@Marting thanx alot, it was excellent solution. Can you guide me in slight modificaiton of above sub query. I just want to keep all conditions as such with one extra condition. Currently opportunitylines.crmAccept should be 1 or 3 i want to also include if there is no opportunitylines with opportunity entity. – Irfan DANISH May 24 '13 at 11:17
1

@IrfanDANISH: Probably something like `"stateCode == 1 AND invoiceDate >= %@ AND (SUBQUERY(opportunitylines, $x, $x.crmAccept == 1 OR $x.crmAccept == 3).@count > 0 OR opportunitylines.@count == 0)"`. – Martin R May 24 '13 at 11:33
1

Thanx during hit and trial i did that :) – Irfan DANISH May 24 '13 at 11:37

Marc · Answer 2 · 2013-05-24T07:25:38.157

The structure of your predicate is A && B && (C || D)

Setup your predicates

NSPredicate *aPredicate = [NSPredicate predicateWithFormat:@"stateCode == %d", value];
NSPredicate *bPredicate = [NSPredicate predicateWithFormat:@"invoiceDate >=  %@", givenDate];

Similar do the cPredicate and dPredicate. Then first combine c and d with OR

NSArray *cdPredicateArray = @[cPredicate, dPredicate];
NSPredicate *cdPredicate = [NSCompoundPredicate orPredicateWithSubpredicates:cdPredicateArray];

and then all of them with AND

NSArray *allPredicateArray = @[aPredicate, bPredicate, cdPredicate];
NSPredicate *allPredicate = [NSCompoundPredicate andPredicateWithSubpredicates:allPredicateArray];

If I misunderstood your question and your structure is A && B && C || D Then you have to combine A, B and C first (with AND) and then combine that result with D (with OR).

Note that the entity name is not part of the predicate, so the first one would be just `... "stateCode == %d", value]`. — Martin R, May 24 '13 at 07:16

score 1 · Answer 3 · answered May 24 '13 at 07:18

You could also fetch your opportunityLines and then get the parent entities like this:

NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"opportunityLines" inManagedObjectContext:context];
[fetchRequest setEntity:entity];

NSDate *yourDate = [NSDate date];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"(crmAccept==1 OR crmaccept==3) AND opportunity.stateCode==1 AND opportunity.invoiceDate>=%@", yourDate];
[fetchRequest setPredicate:predicate];

NSError *error;

//So here you have your array of opportunitylines
NSArray *opportunityLines = [context executeFetchRequest:fetchRequest error:&error];

//And this is how you get your opportunity objects
NSArray *opportunities = [opportunityLines valueForKeyPath:@"@distinctUnionOfObjects.opportunity"];

CoreData NSPredicate with relationship

3 Answers3