9. Performance

Activity 9.01: Optimizing a Query

Solution:

Perform the following steps to complete the activity:

1. Open your mongo shell and connect to the sample_supplies database on the Atlas cluster. First, you need to find how many records the query returns. The following snippet shows a count query, which gives the number of backpacks sold at the Denver store:

        db.sales.count(
            {
                "items.name" : "backpack",
                "storeLocation" : "Denver"
            }
        )
        

2. The query returns a count of 711 records.
3. Next, analyze the query given by the analytics team using the explain() function, and print the execution stats, as...