Create a collection (.NET)

A collection can be created by using the CreateDocumentCollectionAsync method of the DocumentClient class. A collection is a container of JSON documents and associated JavaScript application logic.

async Task CreateCollection(DocumentClient client)
{
    var databaseName = "<your database name>";
    var collectionName = "<your collection name>";

    DocumentCollection collectionInfo = new DocumentCollection();
    collectionInfo.Id = collectionName;

    // Configure collections for maximum query flexibility including string range queries.
    collectionInfo.IndexingPolicy = new IndexingPolicy(new RangeIndex(DataType.String) { Precision = -1 });

    // Here we create a collection with 400 RU/s.
    await client.CreateDocumentCollectionAsync(UriFactory.CreateDatabaseUri(databaseName),
        collectionInfo, new RequestOptions { OfferThroughput = 400 });
}

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Or you can check if the collection exists and create it if necessary:

async Task CreateDocumentCollectionIfNotExists(DocumentClient client)
{
    var databaseName = "<your database name>";
    var collectionName = "<your collection name>";
    try
    {
        await client.ReadDocumentCollectionAsync(UriFactory.CreateDocumentCollectionUri(databaseName, collectionName));
    }
    catch (DocumentClientException e)
    {
        // If the document collection does not exist, create a new collection
        if (e.StatusCode == HttpStatusCode.NotFound)
        {
            DocumentCollection collectionInfo = new DocumentCollection();
            collectionInfo.Id = collectionName;

            // Configure collections for maximum query flexibility including string range queries.
            collectionInfo.IndexingPolicy = new IndexingPolicy(new RangeIndex(DataType.String) { Precision = -1 });

            // Here we create a collection with 400 RU/s.
            await client.CreateDocumentCollectionAsync(UriFactory.CreateDatabaseUri(databaseName),
                collectionInfo, new RequestOptions { OfferThroughput = 400 });
        }
        else
        {
            // Rethrow
            throw;
        }
    }
}