Marten

Searching for NULL Values

Regardless of your feelings about NULL, they do exist in databases and Marten allows you to search for documents that have (or don't have) null values:

public void query_by_nullable_type_nulls(IDocumentSession session)
{
    // You can use Nullable<T>.HasValue in Linq queries
    session.Query<Target>().Where(x => !x.NullableNumber.HasValue).ToArray();
    session.Query<Target>().Where(x => x.NullableNumber.HasValue).ToArray();

    // You can always search by field is NULL
    session.Query<Target>().Where(x => x.Inner == null);
}

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