国外版

算法题（国外版）/bank-account-summary-ii.html

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+<p>Table: <code>Users</code></p>
+
+<pre>
++--------------+---------+
+| Column Name  | Type    |
++--------------+---------+
+| account      | int     |
+| name         | varchar |
++--------------+---------+
+account is the primary key for this table.
+Each row of this table contains the account number of each user in the bank.
+</pre>
+
+<p>&nbsp;</p>
+
+<p>Table: <code>Transactions</code></p>
+
+<pre>
++---------------+---------+
+| Column Name   | Type    |
++---------------+---------+
+| trans_id      | int     |
+| account       | int     |
+| amount        | int     |
+| transacted_on | date    |
++---------------+---------+
+trans_id is the primary key for this table.
+Each row of this table contains all changes made to all accounts.
+amount is positive if the user received money and negative if they transferred money.
+All accounts start with a balance of 0.
+</pre>
+
+<p>&nbsp;</p>
+
+<p>Write an SQL query to report the name and balance of users with a balance higher than <code>10000</code>. The balance of an account is equal to the sum of the amounts of all transactions involving that account.</p>
+
+<p>Return the result table in <strong>any order</strong>.</p>
+
+<p>The query result format is in the following example.</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+
+<pre>
+<strong>Input:</strong> 
+Users table:
++------------+--------------+
+| account    | name         |
++------------+--------------+
+| 900001     | Alice        |
+| 900002     | Bob          |
+| 900003     | Charlie      |
++------------+--------------+
+Transactions table:
++------------+------------+------------+---------------+
+| trans_id   | account    | amount     | transacted_on |
++------------+------------+------------+---------------+
+| 1          | 900001     | 7000       |  2020-08-01   |
+| 2          | 900001     | 7000       |  2020-09-01   |
+| 3          | 900001     | -3000      |  2020-09-02   |
+| 4          | 900002     | 1000       |  2020-09-12   |
+| 5          | 900003     | 6000       |  2020-08-07   |
+| 6          | 900003     | 6000       |  2020-09-07   |
+| 7          | 900003     | -4000      |  2020-09-11   |
++------------+------------+------------+---------------+
+<strong>Output:</strong> 
++------------+------------+
+| name       | balance    |
++------------+------------+
+| Alice      | 11000      |
++------------+------------+
+<strong>Explanation:</strong> 
+Alice&#39;s balance is (7000 + 7000 - 3000) = 11000.
+Bob&#39;s balance is 1000.
+Charlie&#39;s balance is (6000 + 6000 - 4000) = 8000.
+</pre>