Estimate document count (C#)

Estimates the number of documents in a collection.

This method only returns an estimated count. It is an alternative to getting an exact count, which is a slow and expensive operation.

The estimated count is based on current system statistics at the time the request is received by the database server.

Ready to write code? See the examples for this method to get started. If you are new to the Data API, check out the quickstart.

Result

Returns an integer indicating the server-side estimate of the total number of documents in the collection.

Parameters

Use the EstimateDocumentCountAsync method, which belongs to the Collection class. You can also use EstimateDocumentCount, which is the synchronous version of the method.

Method signature
public Task<int> EstimateDocumentCountAsync(
  CollectionEstimateDocumentCountOptions options = null
);
Name Type Summary

options

CollectionEstimateDocumentCountOptions

Optional. General API options for this operation, including the timeout. For more information and examples, see Customize API interaction.

Examples

The following example demonstrates how to estimate the number of documents in a collection.

Estimate document count

using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;

namespace Examples;

public class Program
{
  static async Task Main()
  {
    // Get an existing collection
    var client = new DataAPIClient();
    var database = client.GetDatabase(
      "API_ENDPOINT",
      "APPLICATION_TOKEN"
    );
    var collection = database.GetCollection("COLLECTION_NAME");

    // Estimate count
    var result = await collection.EstimateDocumentCountAsync();

    Console.WriteLine(result);
  }
}

Client reference

For more information, see the client reference.

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