Даны 2 таблицы с названиями orders и products c колонками "order_id", "customer_id", "product_id", "order_date", "quantity" и "product_id", "product_name", "unit_price". Какой из следующих SQL запросов вернет топ-5 покупателей, которые потратили больше всего в категории "Electronics"?
A) SELECT o.customer_id, SUM(o.quantity * p.unit_price) AS total_spent FROM orders o JOIN products p ON o.product_id = p.product_id WHERE p.product_name LIKE '%Electronics%' GROUP BY o.customer_id ORDER BY total_spent DESC LIMIT 5;
B) SELECT o.customer_id, SUM(o.quantity * p.unit_price) AS total_spent FROM orders o JOIN products p ON o.product_id = p.product_id WHERE p.product_id IN (SELECT product_id FROM products WHERE product_name LIKE '%Electronics%') GROUP BY o.customer_id ORDER BY total_spent DESC LIMIT 5;
C) SELECT o.customer_id, SUM(o.quantity * p.unit_price) AS total_spent FROM orders o JOIN products p ON o.product_id = p.product_id WHERE p.product_id IN (SELECT product_id FROM products WHERE product_name LIKE 'Electronics%') GROUP BY o.customer_id ORDER BY total_spent DESC LIMIT 5;
D) SELECT o.customer_id, SUM(o.quantity * p.unit_price) AS total_spent FROM orders o JOIN products p ON o.product_id = p.product_id WHERE p.product_id IN (SELECT product_id FROM products WHERE product_name = 'Electronics') GROUP BY o.customer_id ORDER BY total_spent DESC LIMIT 5;
Даны 2 таблицы с названиями orders и products c колонками "order_id", "customer_id", "product_id", "order_date", "quantity" и "product_id", "product_name", "unit_price". Какой из следующих SQL запросов вернет топ-5 покупателей, которые потратили больше всего в категории "Electronics"?
A) SELECT o.customer_id, SUM(o.quantity * p.unit_price) AS total_spent FROM orders o JOIN products p ON o.product_id = p.product_id WHERE p.product_name LIKE '%Electronics%' GROUP BY o.customer_id ORDER BY total_spent DESC LIMIT 5;
B) SELECT o.customer_id, SUM(o.quantity * p.unit_price) AS total_spent FROM orders o JOIN products p ON o.product_id = p.product_id WHERE p.product_id IN (SELECT product_id FROM products WHERE product_name LIKE '%Electronics%') GROUP BY o.customer_id ORDER BY total_spent DESC LIMIT 5;
C) SELECT o.customer_id, SUM(o.quantity * p.unit_price) AS total_spent FROM orders o JOIN products p ON o.product_id = p.product_id WHERE p.product_id IN (SELECT product_id FROM products WHERE product_name LIKE 'Electronics%') GROUP BY o.customer_id ORDER BY total_spent DESC LIMIT 5;
D) SELECT o.customer_id, SUM(o.quantity * p.unit_price) AS total_spent FROM orders o JOIN products p ON o.product_id = p.product_id WHERE p.product_id IN (SELECT product_id FROM products WHERE product_name = 'Electronics') GROUP BY o.customer_id ORDER BY total_spent DESC LIMIT 5;
Ответить на вопрос можно ниже ⬇️
BY SQL для тестировщика
Warning: Undefined variable $i in /var/www/tg-me/post.php on line 283
I have no inside knowledge of a potential stock listing of the popular anti-Whatsapp messaging app, Telegram. But I know this much, judging by most people I talk to, especially crypto investors, if Telegram ever went public, people would gobble it up. I know I would. I’m waiting for it. So is Sergei Sergienko, who claims he owns $800,000 of Telegram’s pre-initial coin offering (ICO) tokens. “If Telegram does a SPAC IPO, there would be demand for this issue. It would probably outstrip the interest we saw during the ICO. Why? Because as of right now Telegram looks like a liberal application that can accept anyone - right after WhatsApp and others have turn on the censorship,” he says.
How Does Bitcoin Work?
Bitcoin is built on a distributed digital record called a blockchain. As the name implies, blockchain is a linked body of data, made up of units called blocks that contain information about each and every transaction, including date and time, total value, buyer and seller, and a unique identifying code for each exchange. Entries are strung together in chronological order, creating a digital chain of blocks. “Once a block is added to the blockchain, it becomes accessible to anyone who wishes to view it, acting as a public ledger of cryptocurrency transactions,” says Stacey Harris, consultant for Pelicoin, a network of cryptocurrency ATMs. Blockchain is decentralized, which means it’s not controlled by any one organization. “It’s like a Google Doc that anyone can work on,” says Buchi Okoro, CEO and co-founder of African cryptocurrency exchange Quidax. “Nobody owns it, but anyone who has a link can contribute to it. And as different people update it, your copy also gets updated.”