CosmosDB Paging Return Value - rest

Question

I am trying to return paging results the request from CosmosDB. I saw this example from here but I am not sure what to do with the response variable.
// Fetch query results 10 at a time.
var queryable = client.CreateDocumentQuery<Book>(collectionLink, new FeedOptions { MaxItemCount = 10 });
while (queryable.HasResults)
{
FeedResponse<Book> response = await queryable.ExecuteNext<Book>();
}
Am I suppose to return it directly? Or do I have to do something further with the response variable? I tried to return the response variable directly and it's not working. Here's my code:
public async Task<IEnumerable<T>> RunQueryAsync(string queryString)
{
var feedOptions = new FeedOptions { MaxItemCount = 3 };
IQueryable<T> filter = _client.CreateDocumentQuery<T>(_collectionUri, queryString, feedOptions);
IDocumentQuery<T> query = filter.AsDocumentQuery();
var response = new FeedResponse<T>();
while (query.HasMoreResults)
{
response = await query.ExecuteNextAsync<T>();
}
return response;
}
Update:
After reading #Evandro Paula's answer, I followed the URL and changed my implementation to below. But it is still giving me 500 status code:
public async Task<IEnumerable<T>> RunQueryAsync(string queryString)
{
var feedOptions = new FeedOptions { MaxItemCount = 1 };
IQueryable<T> filter = _client.CreateDocumentQuery<T>(_collectionUri, queryString, feedOptions);
IDocumentQuery<T> query = filter.AsDocumentQuery();
List<T> results = new List<T>();
while (query.HasMoreResults)
{
foreach (T t in await query.ExecuteNextAsync())
{
results.Add(t);
}
}
return results;
}
And here's the exception message:
Cross partition query is required but disabled. Please set
x-ms-documentdb-query-enablecrosspartition to true, specify
x-ms-documentdb-partitionkey, or revise your query to avoid this
exception., Windows/10.0.17134 documentdb-netcore-sdk/1.9.1
Update 2:
I added the EnableCrossPartitionQuery to true and I am able to get the response from CosmosDB. But I am not able to get the 1 item that I defined. Instead, I got 11 items.

Answer 1

Find below a simple example on how to use the CosmosDB/SQL paged query:
private static async Task Query()
{
Uri uri = new Uri("https://{CosmosDB/SQL Account Name}.documents.azure.com:443/");
DocumentClient documentClient = new DocumentClient(uri, "{CosmosDB/SQL Account Key}");
int currentPageNumber = 1;
int documentNumber = 1;
IDocumentQuery<Book> query = documentClient.CreateDocumentQuery<Book>("dbs/{CosmoDB/SQL Database Name}/colls/{CosmoDB/SQL Collection Name}", new FeedOptions { MaxItemCount = 10 }).AsDocumentQuery();
while (query.HasMoreResults)
{
Console.WriteLine($"----- PAGE {currentPageNumber} -----");
foreach (Book book in await query.ExecuteNextAsync())
{
Console.WriteLine($"[{documentNumber}] {book.Id}");
documentNumber++;
}
currentPageNumber++;
}
}
Per exception described in your question Cross partition query is required but disabled, update the feed options as follows:
var feedOptions = new FeedOptions { MaxItemCount = 1, EnableCrossPartitionQuery = true};
Find a more comprehensive example at https://github.com/Azure/azure-documentdb-dotnet/blob/d17c0ca5be739a359d105cf4112443f65ca2cb72/samples/code-samples/Queries/Program.cs#L554-L576.

Answer 2

you are not specifying any where criteria for your specific item...so you are getting all results..try specifying criteria for the item (id , name etc) you are looking for. And keep in mind cross partition queries consume much more RUs n time, you can revisit architecture of your data model..Ideally always do queries with in same partition