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SQL Basics
SQL Basics
What is grouping?
Grouping - is arranging observations into sub-groups based on unique values in some column. For example, we can group our audi_cars
table by transmission
column (contains 3 unique values). There will be observations within each subgroup. So, what's the point of grouping?
In SQL grouping is often used in pair with some aggregate function within SELECT
. For example, we can calculate the average price
for each transmission
type.
SELECT AVG(price), transmission FROM audi_cars GROUP BY transmission
This will return all the transmissions types with average prices within each group.
Завдання
From the audi_cars
table calculate the average price
of each model
. Round price to two decimals.
Дякуємо за ваш відгук!
What is grouping?
Grouping - is arranging observations into sub-groups based on unique values in some column. For example, we can group our audi_cars
table by transmission
column (contains 3 unique values). There will be observations within each subgroup. So, what's the point of grouping?
In SQL grouping is often used in pair with some aggregate function within SELECT
. For example, we can calculate the average price
for each transmission
type.
SELECT AVG(price), transmission FROM audi_cars GROUP BY transmission
This will return all the transmissions types with average prices within each group.
Завдання
From the audi_cars
table calculate the average price
of each model
. Round price to two decimals.
Дякуємо за ваш відгук!
What is grouping?
Grouping - is arranging observations into sub-groups based on unique values in some column. For example, we can group our audi_cars
table by transmission
column (contains 3 unique values). There will be observations within each subgroup. So, what's the point of grouping?
In SQL grouping is often used in pair with some aggregate function within SELECT
. For example, we can calculate the average price
for each transmission
type.
SELECT AVG(price), transmission FROM audi_cars GROUP BY transmission
This will return all the transmissions types with average prices within each group.
Завдання
From the audi_cars
table calculate the average price
of each model
. Round price to two decimals.
Дякуємо за ваш відгук!
Grouping - is arranging observations into sub-groups based on unique values in some column. For example, we can group our audi_cars
table by transmission
column (contains 3 unique values). There will be observations within each subgroup. So, what's the point of grouping?
In SQL grouping is often used in pair with some aggregate function within SELECT
. For example, we can calculate the average price
for each transmission
type.
SELECT AVG(price), transmission FROM audi_cars GROUP BY transmission
This will return all the transmissions types with average prices within each group.
Завдання
From the audi_cars
table calculate the average price
of each model
. Round price to two decimals.