Sum, Average, Min/Max Queries

Both the sum and average queries can help us summarize and analyze numerical data in a table.

Total Sum

The SUM() function returns the total sum of a numeric column.

It is useful when calculating how many records from an attribute fits your given condition.

SUM() Query Format

SELECT SUM(column_name) FROM table_name WHERE condition;

Average of an Attribute

The AVG() function returns the average value of a numeric column.

AVG() Query Format

SELECT AVG(column_name) FROM table_name WHERE condition;

Use Cases for SUM() and AVG()

Let us assume that we have the following table:

Products(ProductID, Name, Price, Sold)

• The sum query can be used to output number of products sold so far in the table

SELECT SUM(Sold) FROM Products;

• The average query can be used to output the average price of all items in the table

SELECT AVG(Price) FROM Products;

Minimum and Maximum from an Attribute

The MIN() function returns the smallest value of the selected column.

The MAX() function returns the largest value of the selected column.

Query Format

SELECT MIN(column_name) FROM table_name WHERE condition;

SELECT MAX(column_name) FROM table_name WHERE condition;