SQL Comments

 In SQL, comments are used to add notes or explanations to your code, making it easier to understand. There are two ways to write comments in SQL:

1. Single-line Comments:
   You can use two dashes (--) to add a comment to a single line. Everything after -- on that line will be treated as a comment.

   Example:

   SELECT * FROM Employees; -- This is a comment explaining the query
   

2. Multi-line Comments:
   You can use /* to begin a comment and */ to end it. Everything between these markers is treated as a comment, and it can span multiple lines.

   Example:

   /*
   This is a multi-line comment.
   It can span multiple lines.
   */
   SELECT * FROM Employees;
   

These comments are ignored by the SQL engine and do not affect the execution of the query. They are purely for documentation purposes.