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Please enable JavaScript in your browser settings or update your browser.ROUNDing | Aggregating
SQL Basics
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Contenido del Curso

SQL Basics

SQL Basics

1. Selecting
The very first meet with the databaseSELECTing certain columnsLIMITing resultsUnique values from columnUnique values from multiple columnsHow many?How many unique?AliasesTables aliases
2. Filtering
Word filteringNumber filteringCombining conditionsFiltering by numeric intervalMultiple filtering on one columnLIKE filteringNOT like this!
3. Aggregating
MINimal and MAXimal valuesSUMming valuesMean valuesROUNDing
4. Sorting
Sorting by one columnSorting in DESCending orderThe cheapest carSorting by multiple columns
5. Grouping
What is grouping?More aggregate statistics!Grouping by multiple columnsThe cheapest combinationHAVING some conditionsLeast consuming carsFiltering group size
6. Practicing
Challenge: Unique combinationsChallenge: Average Q-series cars priceChallenge: The cheapest new A-series carsChallenge: Relation between engine size and fuel consumptionChallenge: Mileage and manufacture year - is there relation?Challenge: Average price for each model and yearChallenge: The most expensive transmission + engine size combinations

bookROUNDing

In the last chapter, you solved the task and received a number with many digits after the decimal place. This is surely precise, but not representative, as there is no way to pay 0.002$, for example. It would be great if we could round numbers to some digits.

Surely it's also implemented into SQL! To round number to n decimal places use ROUND(column_name, n) function. For example, from our audi_cars dataset let's calculate the average price of TT model cars with mileage less than 3000 and round the result to 0 decimals (so it will be an integer).


              
123

            
SELECT ROUND(AVG(price), 0)
FROM audi_cars
WHERE model = 'TT' AND mileage < 3000
copy

That's more representative!

Tarea

From the audi_cars table calculate the average price for Petrol cars (column fueltype) with Semi-Auto transmission (column transmission). Round the result to 2 digits after the comma.

Switch to desktopCambia al escritorio para practicar en el mundo realContinúe desde donde se encuentra utilizando una de las siguientes opciones
¿Todo estuvo claro?

¿Cómo podemos mejorarlo?

¡Gracias por tus comentarios!

Sección 3. Capítulo 4
toggle bottom row

bookROUNDing

In the last chapter, you solved the task and received a number with many digits after the decimal place. This is surely precise, but not representative, as there is no way to pay 0.002$, for example. It would be great if we could round numbers to some digits.

Surely it's also implemented into SQL! To round number to n decimal places use ROUND(column_name, n) function. For example, from our audi_cars dataset let's calculate the average price of TT model cars with mileage less than 3000 and round the result to 0 decimals (so it will be an integer).


              
123

            
SELECT ROUND(AVG(price), 0)
FROM audi_cars
WHERE model = 'TT' AND mileage < 3000
copy

That's more representative!

Tarea

From the audi_cars table calculate the average price for Petrol cars (column fueltype) with Semi-Auto transmission (column transmission). Round the result to 2 digits after the comma.

Switch to desktopCambia al escritorio para practicar en el mundo realContinúe desde donde se encuentra utilizando una de las siguientes opciones
¿Todo estuvo claro?

¿Cómo podemos mejorarlo?

¡Gracias por tus comentarios!

Sección 3. Capítulo 4
toggle bottom row

bookROUNDing

In the last chapter, you solved the task and received a number with many digits after the decimal place. This is surely precise, but not representative, as there is no way to pay 0.002$, for example. It would be great if we could round numbers to some digits.

Surely it's also implemented into SQL! To round number to n decimal places use ROUND(column_name, n) function. For example, from our audi_cars dataset let's calculate the average price of TT model cars with mileage less than 3000 and round the result to 0 decimals (so it will be an integer).


              
123

            
SELECT ROUND(AVG(price), 0)
FROM audi_cars
WHERE model = 'TT' AND mileage < 3000
copy

That's more representative!

Tarea

From the audi_cars table calculate the average price for Petrol cars (column fueltype) with Semi-Auto transmission (column transmission). Round the result to 2 digits after the comma.

Switch to desktopCambia al escritorio para practicar en el mundo realContinúe desde donde se encuentra utilizando una de las siguientes opciones
¿Todo estuvo claro?

¿Cómo podemos mejorarlo?

¡Gracias por tus comentarios!

In the last chapter, you solved the task and received a number with many digits after the decimal place. This is surely precise, but not representative, as there is no way to pay 0.002$, for example. It would be great if we could round numbers to some digits.

Surely it's also implemented into SQL! To round number to n decimal places use ROUND(column_name, n) function. For example, from our audi_cars dataset let's calculate the average price of TT model cars with mileage less than 3000 and round the result to 0 decimals (so it will be an integer).


              
123

            
SELECT ROUND(AVG(price), 0)
FROM audi_cars
WHERE model = 'TT' AND mileage < 3000
copy

That's more representative!

Tarea

From the audi_cars table calculate the average price for Petrol cars (column fueltype) with Semi-Auto transmission (column transmission). Round the result to 2 digits after the comma.

Switch to desktopCambia al escritorio para practicar en el mundo realContinúe desde donde se encuentra utilizando una de las siguientes opciones
Sección 3. Capítulo 4
Switch to desktopCambia al escritorio para practicar en el mundo realContinúe desde donde se encuentra utilizando una de las siguientes opciones
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