As is any programming languages comments matter a lot in SQL also. In this set we will learn about writing comments in any SQL snippet.
Comments can be written in the following three formats:
- Single line comments.
- Multi line comments
- In line comments
Single line comments: Comments starting and ending in a single line are considered as single line comments.
Line starting with ‘–‘ is a comment and will not be executed.
--single line comment --another comment SELECT * FROM Customers;
Multi line comments: Comments starting in one line and ending in different line are considered as multi line comments. Line starting with ‘/*’ is considered as starting point of comment and are terminated when ‘*/’ is encountered.
/* multi line comment another comment */ SELECT * FROM Customers;
In line comments: In line comments are an extension of multi line comments, comments can be stated in between the statements and are enclosed in between ‘/*’ and ‘*/’.
SELECT * FROM /* Customers; */
Multi line comment -> /* SELECT * FROM Students; SELECT * FROM STUDENT_DETAILS; SELECT * FROM Orders; */ SELECT * FROM Articles; In line comment -> SELECT * FROM Students; SELECT * FROM /* STUDENT_DETAILS; SELECT * FROM Orders; SELECT * FROM */ Articles;
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