TL;DR – SQL aggregate functions allow you to perform calculations on multiple values and get a single value as a result.
SQL Aggregate Functions Explained
Counting in SQL is very similar to Microsoft Excel. Whenever you need to work with multiple values in the same table row, you can use arithmetical operators (
/). However, if the values are in multiple rows, you will need to use SQL aggregate functions.
Using aggregate functions in SQL, you can apply calculations to whole table columns and work with thousands of rows at once. This is especially helpful when you need to quickly summarize data and see the big picture instead of analyzing individual entries.
Theory is great, but we recommend digging deeper!
Aggregate Functions in SQL: A List
|AVG()||The average of a set of values|
|COUNT()||The number of rows in a column|
|MAX()||The biggest value in a column|
|MIN()||The smallest value in a column|
|SUM()||The sum of values in a column|
SQL Aggregate Functions: Useful Tips
- Before you start working with data, all aggregate functions in SQL have a value of Null.
- You can combine SQL aggregate functions with the ROUND() function to round up numeric values.