Sellers With No Sales - Leetcode Solution

Problem Statement:

The problem is titled "Sellers With No Sales" and it asks us to find the names of all the sellers on an e-commerce platform who have never made a sale. We are given two tables - 'Sellers' and 'Orders'. The Sellers table contains data about all the sellers including their ID, name, and the category of products they sell. The Orders table contains data about all the orders placed including the order ID, the seller ID, and the date on which the order was placed.

We need to write an SQL query to retrieve the names of all the sellers who have not sold any product so far.

Solution:

To solve this problem, we need to join the two tables - Sellers and Orders, using the seller ID as the common field. Then, we need to select only those sellers who do not have any orders placed in their name. In SQL, we can achieve this using a left join and a where condition.

The SQL query to solve the problem is as follows:

SELECT DISTINCT Sellers.name FROM Sellers LEFT JOIN Orders ON Sellers.seller_id = Orders.seller_id WHERE Orders.seller_id IS NULL;

Explanation:

We start with the SELECT keyword and then use the DISTINCT keyword to select only the unique names of the sellers who have not made any sales.

In the FROM clause, we mention the 'Sellers' table which contains the data about all the sellers.

We then use the LEFT JOIN keyword to join the 'Orders' table with the 'Sellers' table. We use the 'seller_id' field from both tables to join them. This will give us a table which contains all the sellers, along with the orders placed by them (if any).

Finally, we use the WHERE clause to select only the rows where the 'seller_id' field in the 'Orders' table is null. This will give us all the sellers who have not made any sales so far.

We use the semicolon at the end of the query to indicate the end of the SQL statement.

In conclusion, the SQL query mentioned above will give us the names of all the sellers who have not made any sales on the e-commerce platform.

1