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Goals

I am trying to achieve the following query:

AttributeCode = 'attributes_2' AND 
Item.ItemId IN { '5e5a7eeac1c88db03896194b', '5e5a7eeac1c88db038961947', '5e5a7eeac1c88db038961949' } AND 
ValueNumber = 101.999

My schema looks like:

class Item {
  [PrimaryKey]
  public string ItemId { get; set; }
  public IList<Attribute> { get; }
}

class Attribute {
  [Backlink(nameof(Item.Attributes))]
  public Item Item { get; }
  [Indexed]
  public string AttributeCode { get; }
  public string? ValueString { get; }
  public bool? ValueBoolean { get; }
  public double? ValueNumber { get; }
}

Unfortunately I cannot use a concrete implementation of the data models coming from our api, they are defined by customers, I just know each item has 0-many attributes. I have found it 15-20 times faster in my tests to query the Attribute realm directly and use the backlink to filter on item id rather than query the Item realm directly then use a subquery statement. I was testing using an OR'd statement previously for the item id e.g.

AttributeCode = 'attributes_2' AND 
( Item.ItemId = '5e5a7eeac1c88db03896194b' OR Item.ItemId = '5e5a7eeac1c88db038961947' OR Item.ItemId = '5e5a7eeac1c88db038961949' ) AND 
ValueNumber = 101.999

does the realm .net sdk (or realm under the hood) not support the IN statement on a backlinked property?

<!--- What are you trying to achieve? -->

Expected Results

For the filter to execute like the more verbose OR statement, the realm cheatsheet https://academy.realm.io/posts/nspredicate-cheatsheet/ suggests excessive use of OR is bad for performance and I may have up to 1k item ids.

A side note, where can I go to find any useful realm query suggestions/recommendations with regards to performance? My data set is ~100k items and 1m attributes.

<!--- What did you expect to happen? -->

Actual Results

I get the exception:

Test	Duration	Traits	Error Message
Realms.Exceptions.RealmException : AttributeCode = 'attributes_2' AND Item.ItemId IN { '5e5a7eeac1c88db03896194b', '5e5a7eeac1c88db038961947', '5e5a7eeac1c88db038961949' } AND ValueNumber = 101.999:1:50(50): Invalid predicate.

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Steps to Reproduce

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Code Sample

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