Recall & Review
beginner
What does the
$add operator do in MongoDB aggregation?The
$add operator adds numbers or dates together. It sums the values of its arguments and returns the total.Click to reveal answer
beginner
How do you multiply two fields in a MongoDB aggregation pipeline?
Use the
$multiply operator with an array of the fields or values you want to multiply. It returns the product.Click to reveal answer
intermediate
What happens if you use
$divide with a divisor of zero?MongoDB returns
null because division by zero is undefined.Click to reveal answer
beginner
Write a MongoDB aggregation expression to calculate the total price by multiplying
quantity and price fields.{ $multiply: ["$quantity", "$price"] }Click to reveal answer
intermediate
Can
$add be used to add dates in MongoDB? How?Yes,
$add can add a number (milliseconds) to a date to get a new date. For example, adding 86400000 (milliseconds in a day) to a date adds one day.Click to reveal answer
Which operator would you use to add two numbers in a MongoDB aggregation?
✗ Incorrect
The
$add operator sums numbers or dates.What does
{ $multiply: [2, 3, 4] } return?✗ Incorrect
It multiplies 2 × 3 × 4 = 24.
What is the result of
{ $divide: [10, 0] } in MongoDB?✗ Incorrect
MongoDB returns
null for division by zero.How would you add 5 days to a date field
startDate?✗ Incorrect
5 days × 86400000 ms/day = 432000000 ms added to the date.
Which operator would you use to calculate the average price by dividing total price by quantity?
✗ Incorrect
Use
$divide to divide total price by quantity.Explain how to use the MongoDB
$add, $multiply, and $divide operators in aggregation pipelines.Think about simple math operations and how they apply to fields or values.
You got /3 concepts.
Describe a real-life example where you might use
$multiply and $divide in a MongoDB aggregation.Consider shopping or sales data.
You got /3 concepts.