NSPredicate execureFetchRequest not working - possibly due to spaces in string - ios

I am trying to search in CoreData for an object that matches both a recordId and a string name, but it doesn't always find the object.
For example, I an searching for an object with id 1000 and name "The Brown Family" (note the 2 spaces between "The" and "Brown").
If I use:
NSPredicate *pred = [NSPredicate predicateWithFormat:#"(recordId == %#") AND (name like[cd] %#)", recordId, name];
with recordId=1000 and name="The Brown Family", the fetch request returns nil.
If I use:
NSPredicate *pred = [NSPredicate predicateWithFormat:#"(recordId == %#"), recordId];
with recordId=1000, it finds the object. If I print the object's name property, I get "The Brown Family".
So the object is there with the correct id and name, but my fetchRequest fails.
What am I doing wrong?

You might need to enclose the value in single quotes...
NSPredicate *pred = [NSPredicate predicateWithFormat:#"(recordId == %#) AND (name like[cd] '%#')", recordId, name];

Sorry but I realise what the problem is now! The name I was searching for had a trailing space after it. So I was looking for say "Toby " whereas "Toby" was stored in Coredata.
Sorry for wasting everyone's time.

Related

How to set predicate for a string attribute holding integer value in core data

How to set predicate for a string attribute holding integer value in core data to get the in-between values in integer.
I am using compound predicate for multiple conditions and a piece of code follows..
NSPredicate *categoryPredicate = [NSPredicate predicateWithFormat: #"rating >= %# AND rating <= %#",ratingFrom.text,ratingTo.text];
[compoundPredicateArray addObject: categoryPredicate ];
"rating" attribute is of type string in database. I need to get the rating between the given range in the ratingFrom & ratingTo textfields.
"1" to "10" should fetch all ratings in between 1 to 10.how can I achieve this, without changing the attribute type to number.
Any help appreciated..Thanks
i am not confirm but try this
convert your values in NSString and put this code
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"string CONTAINS[c] %#",searchText];
Ideally you should change this attribute to be a number rather than a string. But if that's not possible, the following should force CoreData (or rather SQLite) to treat it as a number:
NSPredicate *categoryPredicate = [NSPredicate predicateWithFormat: #"add:to:(rating,0) >= %d AND add:to:(rating,0) <= %d",ratingFrom.text.intValue,ratingTo.text.intValue];
you can try BETWEEN expression:
BETWEEN The left-hand expression is between, or equal to either of,
the values specified in the right-hand side. The right-hand side is a
two value array (an array is required to specify order) giving upper
and lower bounds. For example, 1 BETWEEN { 0 , 33 }, or $INPUT BETWEEN
{ $LOWER, $UPPER }. In Objective-C, you could create a BETWEEN
predicate as shown in the following example:
So your code should look like this:
NSPredicate *betweenPredicate =
[NSPredicate predicateWithFormat: #"rating BETWEEN %#", #[ratingFrom, ratingTo]];
ratingFrom, ratingTo should be NSNumber instances if rating is NSNumber.

NSPredicate - Return inexact matches

In my app I allow users to search for vehicles by make/model using a textfield keyword search. Here is my predicate:
if (self.keywordSearch.text.length > 0) {
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"fields.make CONTAINS[cd] %# OR fields.model CONTAINS[cd] %#", self.keywordSearch.text, self.keywordSearch.text];
self.vehicleArray = [[self.vehicleArray filteredArrayUsingPredicate:predicate] mutableCopy];
}
The problem is that if the Vehicle make/model is 'Ford F-150' and the user searches F150, or F 150, the vehicle isn't included in the results. It only returns if they search F-150 or f-150.
Is there a way to make sure these inexact matches are returning?
I suggest using regular expressions for this. You can either use a regular expression literal inside the NSPredicate format (described here: https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/Predicates/Articles/pUsing.html ) or you can iterate the array manually and use an NSRegularExpression for comparing the strings.

NSPredicate and BEGINSWITH with CloudKit : Field value type mismatch

I have a table "Store" with the attributes "name" of type String (indexes checked for sort query and search).
I want to execute a SQL like query to find all stores with name beginning with a substring.
So I tried this predicate :
NSPredicate *pred = [NSPredicate predicateWithFormat:#"ANY name BEGINSWITH %#",substring];
CKQuery *query = [[CKQuery alloc]initWithRecordType:#"Store" predicate:pred];
CKQueryOperation *queryOperation = [[CKQueryOperation alloc] initWithQuery:query];
queryOperation.desiredKeys = #[#"name",#"category"];
NSMutableArray *results = [[NSMutableArray alloc] init];
queryOperation.recordFetchedBlock = ^(CKRecord *record) {
[results addObject:record];
};
queryOperation.queryCompletionBlock = ^(CKQueryCursor *cursor, NSError *error) {
//my own code
}
[publicDatabase addOperation:queryOperation];
I have this error :
<CKError 0x1887a540: "Invalid Arguments" (12/1009); "Field value type mismatch in query predicate for field 'name'"> for query : <CKQuery: 0x18882650; recordType=Store, predicate=ANY name BEGINSWITH "mysubstring">
My guess is that you need to get rid of the "ANY".
The ANY and SOME aggregate operators may be combined with the IN and
CONTAINS operators to perform list membership tests.
So ANY is for lists (Arrays). Since 'name' is a String, it is not a list, hence the mismatch error: "Field value type mismatch in query predicate for field 'name'"
Wild guess...try:
[NSPredicate predicateWithFormat:#"ANY {'name','category'} BEGINSWITH %#",substring];
That may be an incorrect reversal of key/value but it might work.
A completely different approach would be to create a third field called "nameAndCategory", append the two strings and add them to the field. Then figure out how to do the full text search (tokenized string search) with the predicate:
[NSPredicate predicateWithFormat:#"self contains '%#'",substring];
or
[NSPredicate predicateWithFormat:[NSString stringWithFormat:#"self contains '%#'",substring];
But perhaps the only sure approach is to do two searches and combine the results.

NSPredicate with dynamic key and value

I am trying to create a function that searches through my core data stack and return the amount of messages for a desired key/value.
Here is my code:
NSFetchRequest *messagesCountRequest = [NSFetchRequest fetchRequestWithEntityName:#"Message"];
NSEntityDescription *messageCountModel = [NSEntityDescription entityForName:#"Message" inManagedObjectContext:_mainManagedObjectContext];
[messagesCountRequest setEntity:messageCountModel];
NSPredicate *messageCountPredicate = [NSPredicate predicateWithFormat:#"%# == %#", key, value];
[messagesCountRequest setPredicate:messageCountPredicate];
count = (int)[_mainManagedObjectContext countForFetchRequest:messagesCountRequest error:nil];
The problem is that it returns 0 every time. I have located the source of the problem. When have a static key, the predicate looks like this.
key == "value"
When I pass through a dynamic key, it looks like this
"key" == "value"
So the problem appears to be the first set of double quotes around the key that is placed by passing a NSString to the predicate. How would I fix this?
EDIT: For clarity, I need it to be like the first case, that is the one that works.
To substitute a key in the predicate string, you have to use %K, not %#:
[NSPredicate predicateWithFormat:#"%K == %#", key, value];
From the Predicate Format String Syntax documentation:
%# is a var arg substitution for an object value—often a string, number, or date.
%K is a var arg substitution for a key path.
let predicate = NSPredicate(format: "SELF[%#] CONTAINS %#",key,value)
This worked for me

NSPredicate for a Core Data Search

I have 3 NSManagedObjets; Person, Stuff, and Collection.
I want to use a NSPredicate to get a list of all Collections that ThePerson has.
Example: Scott has objectA and objectB which are in collection Letters and object1 which is in collection Numbers.
I want to be able to do a fetch request and get back collection Letters and Numbers.
I tried:
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"ANY stuffs.persons == %#", person];
And:
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"SUBQUERY(stuffs, $s, ANY $s.persons == %#)", scott];
Any suggestions?
Your SUBQUERY syntax is wrong (for a full explanation, see this answer or this answer). It should be something like:
SUBQUERY(stuffs, $s, ANY $s.persons == %#).#count > 0
Since it seems that you already have a reference to a ThePerson object, you don't need to do a fetch or use a predicate. You can traverse the relationships you've declared to get the collections. You can get all of the Collections that ThePerson has by using:
NSSet *collections = [person valueForKeyPath:#"stuffs.collections"];

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