Job-Ready SQL in an Afternoon - Aggregation Functions

The video tutorial explores various SQL aggregation functions, including AVG, MAX, MIN, SUM, and COUNT, to analyze data in a track table. It demonstrates how to calculate average, maximum, and minimum durations, sum total times, and count instances, while addressing null values. Additionally, it covers converting milliseconds to fractional minutes using arithmetic operations.

What is the primary purpose of using aggregations in SQL?

• To modify the structure of the database

• To create new tables

• To perform calculations on data sets

• To delete data from tables

Which SQL function is used to find the average value of a column?

• AVG

• MIN

• COUNT

• SUM

How can you find the longest time in a column using SQL?

• Using the MIN function

• Using the COUNT function

• Using the MAX function

• Using the AVG function

What does the COUNT function do in SQL?

• It counts the number of occurrences in a column

• It finds the average of a column

• It sums up all values in a column

• It finds the maximum value in a column

How do null values affect the COUNT function in SQL?

• They are included in the count

• They are ignored in the count

• They cause an error

• They double the count

What is one way to count the total number of rows in a table?

• Using the MIN function

• Using the MAX function

• Using a star (*) in the COUNT function

• Using the AVG function

How can you convert milliseconds to minutes in SQL?

• By multiplying by 1000 and then by 60

• By adding 1000 and then 60

• By subtracting 1000 and then 60

• By dividing by 1000 and then by 60