Query Advisor for Azure Cosmos DB for NoSQL

Usage example

string query = "SELECT VALUE r.id FROM root r WHERE CONTAINS(r.name, 'Abc')";

QueryRequestOptions requestOptions = new QueryRequestOptions() { PopulateQueryAdvice = true };

using FeedIterator<CosmosElement> itemQuery = testContainer.GetItemQueryIterator<CosmosElement>(
    query,
    requestOptions: requestOptions);

string queryAdvice = null;
while (itemQuery.HasMoreResults)
{
    if (queryAdvice != null)
    {
        break;
    }

    FeedResponse<Item> page = await itemQuery.ReadNextAsync();
    queryAdvice = page.QueryAdvice;
}

Console.WriteLine(queryAdvice);

Example output

In this example query, we observe that there's one single advice, called QA1002:

QA1002: Instead of CONTAINS, consider using STARTSWITH or computed properties, which may improve performance. [...]

The query advice contains three important pieces of information:

• The Query Advice ID: QA1002
• The advice description: "Instead of..."
• The link to the documentation: A URL to detailed guidance

We encourage you to visit the provided link to learn more about the query advice where you can see further examples, detailed explanations, and suggestions to improve your query.

Additional examples

Optimizing system functions

Query:

SELECT GetCurrentTicks() 
FROM root r 
WHERE GetCurrentTimestamp() > 10

Query Advice:

QA1009: Instead of using GetCurrentTimestamp, consider using GetCurrentTimestampStatic, which may improve performance. [...]

QA1008: Instead of using GetCurrentTicks, consider using GetCurrentTicksStatic, which may improve performance. [...]

In this example, there are 2 pieces of advice returned by the Query Advisor, QA1008 and QA1009. Each piece of advice is separated into a new line in the QueryAdvice string.

Related content

• Query metrics
• Index metrics