Alex
73 lines
2.5 KiB
SQL
73 lines
2.5 KiB
SQL
create table products_extended (
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id INT primary key,
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name VARCHAR(50) not null,
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category VARCHAR(50) not null,
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price INT,
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in_stock BOOLEAN default true,
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email_support VARCHAR(50)
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);
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insert into products_extended (id, name, category, price, in_stock, email_support)
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values (1, 'iPhone 14', 'smartphone', 799, true, 'iphone@apple.com'),
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(2, 'MacBook Air', 'laptop', 1199, false, NULL),
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(3, 'Galaxy S22', 'smartphone', 699, true, 'galaxy@support.com'),
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(4, 'ThinkPad X1', 'laptop', 1399, true, 'thinkpad@lenovo.com'),
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(5, 'iPad Pro', 'tablet', 999, false, 'ipad@apple.com'),
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(6, 'Kindle Paperwhite', 'ebook_reader', 149, true, NULL),
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(7, 'Mi Band 7', 'smartwatch', 49, true, 'miband@xiaomi.com'),
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(8, 'Surface Pro', 'tablet', 1299, true, 'surface@microsoft.com'),
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(9, 'Honor Pad X9', 'tablet', 219, true, 'honor@support.com'),
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(10, 'Dell XPS 13', 'laptop', 1099, false, 'dell@support.com');
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alter table products_extended
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alter column price type DECIMAL(10, 2)
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------------------ Задание №1 (По нему ты говорил, что нечитаемо, объясни как переделать pls <3)
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with email_false as (select * from
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(
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select category, name, price, email_support,
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row_number() over (partition by category order by price desc) as rn
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from products_extended
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where email_support is null)
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where rn = 1
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),
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email_true as (select * from
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(
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select category, name, price, email_support,
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row_number() over (partition by category order by price desc) as rn
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from products_extended
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where email_support is not null)
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where rn = 1
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)
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select category, name, price, email_support from email_false
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union all
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select category, name, price, email_support from email_true
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order by category, price desc
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---------------------- Задание №2 (Переделал с двух оконок в одном запросе на СТЕ с одной оконкой внутри)
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with get_data as (
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select name, category, price,
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LEAD(price) OVER (PARTITION BY category order by price) AS next_price
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from products_extended
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)
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select name, category, price, next_price,
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price - next_price AS diff
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from get_data
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--------------------- Задание №3
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select category, name, price,
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SUM(price) over (partition by category order by price) as cumulative_sales
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from products_extended
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---------------------- Задание №4
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with get_data as (
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select category, name, price, AVG(price) over (partition by category) as avg_price
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from products_extended
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)
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select category, name, price, avg_price,
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case when price > avg_price then 'true' else 'false' end as is_above_avg
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from get_data
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