Зміст курсу

SQL Basics

1. Selecting

The very first meet with the database SELECTing certain columns LIMITing results Unique values from column Unique values from multiple columns How many?How many unique?Aliases Tables aliases

2. Filtering

Word filtering Number filtering Combining conditions Filtering by numeric interval Multiple filtering on one column LIKE filtering NOT like this!

3. Aggregating

MINimal and MAXimal values SUMming values Mean values ROUNDing

4. Sorting

Sorting by one column Sorting in DESCending order The cheapest car Sorting by multiple columns

5. Grouping

What is grouping?More aggregate statistics!Grouping by multiple columns The cheapest combination HAVING some conditions Least consuming cars Filtering group size

6. Practicing

Challenge: Unique combinations Challenge: Average Q-series cars price Challenge: The cheapest new A-series cars Challenge: Relation between engine size and fuel consumption Challenge: Mileage and manufacture year - is there relation?Challenge: Average price for each model and year Challenge: The most expensive transmission + engine size combinations

The cheapest car

Remember the task from the third section, where you calculated the maximum price of a Diesel car? What if we want to see not only the price, but also what model, mileage, and other characteristics of this car?

One of the ways to solve it - is using nested queries, but this is not the topic for this course. Easier, you can order your table in descending order and limit the number of rows to 1! For example,


              12345
            
SELECT *
FROM audi_cars
WHERE fueltype = 'Diesel'
ORDER BY price DESC
LIMIT 1

This query will return all the Diesel cars, ordered by price in descending order with only 1 row! This is the car we were looking for.

Завдання

From the audi_cars table extract the information for the cheapest car with Semi-Auto transmission.

Завдання

From the audi_cars table extract the information for the cheapest car with Semi-Auto transmission.

Перейдіть на комп'ютер для реальної практикиПродовжуйте з того місця, де ви зупинились, використовуючи один з наведених нижче варіантів

Все було зрозуміло?

Секція 4. Розділ 3

The cheapest car

One of the ways to solve it - is using nested queries, but this is not the topic for this course. Easier, you can order your table in descending order and limit the number of rows to 1! For example,


              12345
            
SELECT *
FROM audi_cars
WHERE fueltype = 'Diesel'
ORDER BY price DESC
LIMIT 1

This query will return all the Diesel cars, ordered by price in descending order with only 1 row! This is the car we were looking for.

Завдання

From the audi_cars table extract the information for the cheapest car with Semi-Auto transmission.

Завдання

From the audi_cars table extract the information for the cheapest car with Semi-Auto transmission.

Все було зрозуміло?

Секція 4. Розділ 3

The cheapest car

One of the ways to solve it - is using nested queries, but this is not the topic for this course. Easier, you can order your table in descending order and limit the number of rows to 1! For example,


              12345
            
SELECT *
FROM audi_cars
WHERE fueltype = 'Diesel'
ORDER BY price DESC
LIMIT 1

This query will return all the Diesel cars, ordered by price in descending order with only 1 row! This is the car we were looking for.

Завдання

From the audi_cars table extract the information for the cheapest car with Semi-Auto transmission.

Завдання

From the audi_cars table extract the information for the cheapest car with Semi-Auto transmission.

Все було зрозуміло?

One of the ways to solve it - is using nested queries, but this is not the topic for this course. Easier, you can order your table in descending order and limit the number of rows to 1! For example,


              12345
            
SELECT *
FROM audi_cars
WHERE fueltype = 'Diesel'
ORDER BY price DESC
LIMIT 1

This query will return all the Diesel cars, ordered by price in descending order with only 1 row! This is the car we were looking for.

Завдання

From the audi_cars table extract the information for the cheapest car with Semi-Auto transmission.

Секція 4. Розділ 3