What if we want to filter grouped observations based on some condition? For example, we want to extract only those models available with Hybrid fuel types.

You can do it by grouping firstly by model, and then by fuel type filtered by condition on `fueltype`.

SELECT model
FROM audi_cars
GROUP BY model, fueltype
HAVING fueltype = 'Hybrid'

> Please note, that you can use all the operators learned in the second section within `HAVING` statement.

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.

HAVING some conditions

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