More aggregate statistics!

Can we calculate more than one aggregate statistic while grouping? Surely we can!

For example, from the audi_cars table, we can calculate the maximum price and tax for each year.


              123
            
SELECT AVG(price) AS "avg_price", AVG(tax) AS "avg_tax", year
FROM audi_cars
GROUP BY year

Please note, while grouping you can put non-aggregated function within SELECT statement only if it figures within GROUP BY, otherwise - it has to be aggregated.

Also note, that in the example above without aliases (AS) there will be two columns with identical names, which is unacceptable in SQL.

Another note: you can use aggregate functions for ordering after GROUP BY statement. It will filter based on calculations within groups.

Tehtävä

Swipe to start coding

From the audi_cars table find out the minimum and the maximum prices for each model. Sort in descending order by minimum price.

Ratkaisu

Vaihda työpöytään todellista harjoitusta vartenJatka siitä, missä olet käyttämällä jotakin alla olevista vaihtoehdoista

Oliko kaikki selvää?

Kiitos palautteestasi!

Osio 5. Luku 2

More aggregate statistics!

Can we calculate more than one aggregate statistic while grouping? Surely we can!

For example, from the audi_cars table, we can calculate the maximum price and tax for each year.


              123
            
SELECT AVG(price) AS "avg_price", AVG(tax) AS "avg_tax", year
FROM audi_cars
GROUP BY year

Please note, while grouping you can put non-aggregated function within SELECT statement only if it figures within GROUP BY, otherwise - it has to be aggregated.

Also note, that in the example above without aliases (AS) there will be two columns with identical names, which is unacceptable in SQL.

Another note: you can use aggregate functions for ordering after GROUP BY statement. It will filter based on calculations within groups.

Tehtävä

Swipe to start coding

From the audi_cars table find out the minimum and the maximum prices for each model. Sort in descending order by minimum price.

Ratkaisu

Vaihda työpöytään todellista harjoitusta vartenJatka siitä, missä olet käyttämällä jotakin alla olevista vaihtoehdoista

Oliko kaikki selvää?

Kiitos palautteestasi!

Osio 5. Luku 2

Vaihda työpöytään todellista harjoitusta vartenJatka siitä, missä olet käyttämällä jotakin alla olevista vaihtoehdoista