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/*...*/ (Comment) (Transact-SQL)

Indicates user-provided text. The text between the /* and */ is not evaluated by the server.

Topic link iconTransact-SQL Syntax Conventions

Syntax

/*
text_of_comment
*/

Arguments

  • text_of_comment
    Is the text of the comment. This is one or more character strings.

Remarks

Comments can be inserted on a separate line or within a Transact-SQL statement. Multiple-line comments must be indicated by /* and */. A stylistic convention often used for multiple-line comments is to begin the first line with /*, subsequent lines with **, and end with */.

There is no maximum length for comments.

Nested comments are supported. If the /* character pattern occurs anywhere within an existing comment, it is treated as the start of a nested comment and, therefore, requires a closing */ comment mark. If the closing comment mark does not exist, an error is generated.

For example, the following code generates an error.

DECLARE @comment AS varchar(20);
GO
/*
SELECT @comment = '/*';
*/ 
SELECT @@VERSION;
GO 

To work around this error, make the following change.

DECLARE @comment AS varchar(20);
GO
/*
SELECT @comment = '/*';
*/ */
SELECT @@VERSION;
GO 

Examples

The following example uses comments to explain what the section of the code is supposed to do.

USE AdventureWorks2008R2;
GO
/*
This section of the code joins the Person table with the Address table, 
by using the Employee and BusinessEntityAddress tables in the middle to 
get a list of all the employees in the AdventureWorks2008R2 database 
and their contact information.
*/
SELECT p.FirstName, p.LastName, a.AddressLine1, a.AddressLine2, a.City, a.PostalCode
FROM Person.Person AS p
JOIN HumanResources.Employee AS e ON p.BusinessEntityID = e.BusinessEntityID 
JOIN Person.BusinessEntityAddress AS ea ON e.BusinessEntityID = ea.BusinessEntityID
JOIN Person.Address AS a ON ea.AddressID = a.AddressID;
GO