Comments

 

Now that we know how to execute SQL statements, we are ready to start learning some SQL commands. However, before we do that, there’s one more concept that I’ll like to cover - comments.

 

As mentioned previously, the first line in the code that we wrote (-- Using SELECT to display messages) is a comment.

 

Comments are written to make our code more readable for other programmers. They are meant for humans only and are ignored by the DBMS.

 

To add comments to our program, we type two hyphens, followed by a space, as demonstrated in the example above.

 

Alternatively, we can also use the # symbol as shown below:

 

# This is another way to add comment

 

Last, but not least, if we want to type multiple lines comments, we can use the /*...*/ symbols:

 

/* This is a comment

This is also a comment

This is the third comment */