Mechanical Engineer

Meta

Table: Sales +-------------+-------+ | Column Name | Type | +-------------+-------+ | sale_id | int | | product_id | int | | year | int | | quantity | int | | price | int | +-------------+-------+ (sale_id, year) is the primary key (combination of columns with unique values) of this table. product_id is a foreign key (reference column) to Product table. Each row of this table shows a sale on the product product_id in a certain year. Note that the price is per unit. Table: Product +--------------+---------+ | Column Name | Type | +--------------+---------+ | product_id | int | | product_name | varchar | +--------------+---------+ product_id is the primary key (column with unique values) of this table. Each row of this table indicates the product name of each product. Write a solution to select the product id, year, quantity, and price for the first year of every product sold. Return the resulting table in any order. Example: Sales table: +---------+------------+------+----------+-------+ | sale_id | product_id | year | quantity | price | +---------+------------+------+----------+-------+ | 1 | 100 | 2008 | 10 | 5000 | | 2 | 100 | 2009 | 12 | 5000 | | 7 | 200 | 2011 | 15 | 9000 | Product table: +------------+--------------+ | product_id | product_name | +------------+--------------+ | 100 | Nokia | | 200 | Apple | | 300 | Samsung | Output: +------------+------------+----------+-------+ | product_id | first_year | quantity | price | +------------+------------+----------+-------+ | 100 | 2008 | 10 | 5000 | | 200 | 2011 | 15 | 9000 | `

Meta

Let's design a stories feature, similar to Instagram or WhatsApp. These stories should disappear after a friend views them and only be available for 24 hours after publishing. Consider the following aspects: Functionality: How would users create and upload stories (photos and videos)? How would users view stories from their friends? How would you implement the 24-hour expiration? How would you handle the disappearing aspect after viewing? Scalability: How would you handle a large number of users uploading and viewing stories simultaneously? How would you efficiently store and retrieve stories? How would you manage the storage as stories expire? Data Model: What database schema would you use to store story information (user, timestamp, media URL, view status)? How would you track which users have viewed a story? Technical Challenges: What are the potential challenges in implementing this feature? How would you address issues like latency, storage limitations, and data consistency? Edge Cases: How would you handle users with slow internet connections? What happens if a user uploads a story right before the 24-hour mark? How would you handle deleted user accounts and their associated stories?

Meta

Where are you from in the US?