.Net New Feature: VectorStore - Support for `.Any()` Method in Filters

[pawap90]

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name: VectorStore - Support for .Any() Method in Filters
about: Add support for Enumerable.Any() in VectorStore LINQ filters to enable dynamic array matching against list/array columns

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Feature Request

Currently, VectorStoreCollection LINQ-based filters do not support the .Any() method in filter expressions when working with array/list properties. This limitation prevents filtering on collections where dynamic arrays need to be matched against columns with list/array data types.

Problem

When attempting to use .Any() method in filter expressions for PostgreSQL vector store operations, the following exception is thrown:

System.NotSupportedException : Unsupported method call: Enumerable.Any
   at Microsoft.SemanticKernel.Connectors.SqlFilterTranslator.TranslateMethodCall(MethodCallExpression methodCall, Boolean isSearchCondition)
   at Microsoft.SemanticKernel.Connectors.SqlFilterTranslator.Translate(Expression node, Boolean isSearchCondition)
   at Microsoft.SemanticKernel.Connectors.SqlFilterTranslator.Translate(Boolean appendWhere)
   at Microsoft.SemanticKernel.Connectors.PgVector.PostgresSqlBuilder.BuildSelectWhereCommand[TRecord](NpgsqlCommand command, String schema, String tableName, CollectionModel model, Expression`1 filter, Int32 top, FilteredRecordRetrievalOptions`1 options)

Example Scenario

Consider the following data model:

protected class VectorStoreRecord
{
    [VectorStoreKey]
    public required int Id { get; set; }

    [VectorStoreData(StorageName = "tags")]
    public List<string> Tags { get; set; } = [];

    [VectorStoreData]
    public required string Text { get; set; }
}

Sample data:

new VectorStoreRecord
{
    Id = 1,
    Tags = [ "manual", "pdf", "introduction" ],
    Text = "Chapter 1: Introduction..."
},
new VectorStoreRecord
{
    Id = 2,
    Tags = [ "manual", "pdf", "installation" ],
    Text = "Chapter 2: Installation..."
}

Here's where the exception is thrown:

private readonly VectorStoreCollection<int, VectorStoreRecord> collection;

/* ... */

string[] tagsToFilter = ["pdf", "introduction", "faq"];
await foreach (var result in collection.GetAsync(
    filter: r => r.Tags.Any(tag => tagsToFilter.Contains(tag)), // Throws NotSupportedException
    top: 10
))

Note: This issue was specifically tested and reproduced using the PostgreSQL vector store implementation.

Test repo

You can find a minimal reproduction of this issue in the following repository:
SemanticKernel.PostgresVectorStore.FilterTests

Questions

1. Are there plans to expand LINQ method support in PostgreSQL vector store filters?
2. Would the team be open to a community contribution implementing this feature?

Thank you for considering this enhancement!