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Table: Activity +---------------+---------+ | Column Name | Type | +---------------+---------+ | user_id | int | | session_id | int | | activity_date | date | | activity_type | enum | +---------------+---------+ There is no primary key for this table, it may have duplicate rows. The activity_type column is an ENUM of type ('open_session', 'end_session', 'scroll_down', 'send_message'). The table ..

Market Analysis I - LeetCode Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview. leetcode.com Table: Users +----------------+---------+ | Column Name | Type | +----------------+---------+ | user_id | int | | join_date | date | | favorite_brand | varchar | +----------------+---------+ user_id is the primary ..

Bank Account Summary II - LeetCode Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview. leetcode.com Table: Users +--------------+---------+ | Column Name | Type | +--------------+---------+ | account | int | | name | varchar | +--------------+---------+ account is the primary key for this table. Each row of..

Table: Visits +-------------+---------+ | Column Name | Type | +-------------+---------+ | visit_id | int | | customer_id | int | +-------------+---------+ visit_id is the primary key for this table. This table contains information about the customers who visited the mall. Table: Transactions +----------------+---------+ | Column Name | Type | +----------------+---------+ | transaction_id | int ..

Table Activities: +-------------+---------+ | Column Name | Type | +-------------+---------+ | sell_date | date | | product | varchar | +-------------+---------+ There is no primary key for this table, it may contain duplicates. Each row of this table contains the product name and the date it was sold in a market. Write an SQL query to find for each date the number of different products sold and..

Tree Node - LeetCode Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview. leetcode.com Table: Tree +-------------+------+ | Column Name | Type | +-------------+------+ | id | int | | p_id | int | +-------------+------+ id is the primary key column for this table. Each row of this table contains information a..