/// <summary>
/// Sums the values of a selected field for a given filtered collection of documents.
/// </summary>
/// <typeparam name="TDocument">The type representing a Document.</typeparam>
/// <param name="filter">A LINQ expression filter.</param>
/// <param name="selector">The field you want to sum.</param>
/// <param name="partitionKey">The partition key of your document, if any.</param>
public virtual async Task <int> SumByAsync <TDocument>(Expression <Func <TDocument, bool> > filter,
Expression <Func <TDocument, int> > selector,
string partitionKey = null)
where TDocument : IDocument <TKey>
{
return(await MongoDbReader.SumByAsync <TDocument, TKey>(filter, selector, partitionKey));
}
/// <summary>
/// Sums the values of a selected field for a given filtered collection of documents.
/// </summary>
/// <typeparam name="TDocument">The type representing a Document.</typeparam>
/// <typeparam name="TKey">The type of the primary key.</typeparam>
/// <param name="filter">A LINQ expression filter.</param>
/// <param name="selector">The field you want to sum.</param>
/// <param name="partitionKey">The partition key of your document, if any.</param>
/// <param name="cancellationToken">An optional cancellation Token.</param>
public virtual async Task <int> SumByAsync <TDocument, TKey>(Expression <Func <TDocument, bool> > filter,
Expression <Func <TDocument, int> > selector,
string partitionKey = null,
CancellationToken cancellationToken = default)
where TDocument : IDocument <TKey>
where TKey : IEquatable <TKey>
{
return(await MongoDbReader.SumByAsync <TDocument, TKey>(filter, selector, partitionKey, cancellationToken));
}