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+<h2><a href="https://leetcode.com/problems/product-sales-analysis-iii/">1070. Product Sales Analysis III</a></h2><h3>Medium</h3><hr><div class="sql-schema-wrapper__3VBi"><a class="sql-schema-link__3cEg">SQL Schema<svg viewBox="0 0 24 24" width="1em" height="1em" class="icon__1Md2"><path fill-rule="evenodd" d="M10 6L8.59 7.41 13.17 12l-4.58 4.59L10 18l6-6z"></path></svg></a></div><div><p>Table: <code>Sales</code></p>
+
+<pre>+-------------+-------+
+| 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 <code>Product</code> 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.
+</pre>
+
+<p>&nbsp;</p>
+
+<p>Table: <code>Product</code></p>
+
+<pre>+--------------+---------+
+| 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.
+</pre>
+
+<p>&nbsp;</p>
+
+<p>Write a solution to select&nbsp;the <strong>product id</strong>, <strong>year</strong>, <strong>quantity</strong>, and <strong>price</strong> for the <strong>first year</strong> of every product sold.</p>
+
+<p>Return the resulting table in <strong>any order</strong>.</p>
+
+<p>The&nbsp;result format is in the following example.</p>
+
+<p>&nbsp;</p>
+<p><strong class="example">Example 1:</strong></p>
+
+<pre><strong>Input:</strong> 
+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      |
++------------+--------------+
+<strong>Output:</strong> 
++------------+------------+----------+-------+
+| product_id | first_year | quantity | price |
++------------+------------+----------+-------+ 
+| 100        | 2008       | 10       | 5000  |
+| 200        | 2011       | 15       | 9000  |
++------------+------------+----------+-------+
+</pre>
+</div>