The next function we will talk about - is mean. Mean (average) is probably one of the most simple and usable statistics in real life.

For example, for our `audi_cars` table, we can calculate the average mileage for cars manufactured in 2020. To calculate the average use `AVG` function followed by column name.

SELECT AVG(mileage)
FROM audi_cars
WHERE year = 2020

SQL is a domain-specific programming language widely used by data scientists, analysts, etc for manipulating and extracting necessary data. Nowadays, SQL is a must-have point in the CV for every potential analyst, data scientist. In this course, you will be introduced to the very basics of SQL.

In this section, you will be introduced to the very basics of SQL: extracting one or multiple columns from a database.

In this section, you will learn how to filter observations so only necessary rows will be extracted.

In this section, you will learn about the usage of different aggregating functions for your table, such as minimum, maximum, average... 

In this section, you will learn how to sort your table, even having filters and aggregate functions applied to a table.

In this section, you will learn about grouping observations and usage of this principle.

This chapter is designed for users who have completed the previous sections and want to consolidate knowledge.

Mean values

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