SQL_TEST_WORK

select * from people
where age > 25

select * from people
where age > 25 and age < 45

select * from flats
where floor == 1

select * from flats 
where rooms > 2

select * from cars
where width > 400

select * from cars
where year_created > 2008

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select count (id) from people

select min (age) from people

select count (rooms) from flats
where rooms == 3

select avg (age) from people

select sum (width) from cars

select name from people
where name like 'A%'

select surname from people
where surname like '%T%'

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select * from cars
where people_id in 
(select id from flats where rooms == 3)

select * from cars
where people_id in
(select people_id 
 from cars
 group by people_id
 having count(*)> 1)

select *
from flats
join people
where people.year > 2000

select *
from flats
inner join people on cars.owner_id = people.people_num
left join cars on people.people_num = cars.owner_id
where cars.year_created > 2012