-- (Comment) (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Indicates user-provided text. Comments can be inserted on a separate line, nested at the end of a Transact-SQL command line, or within a Transact-SQL statement. The server does not evaluate the comment.

Transact-SQL syntax conventions

Syntax

-- text_of_comment  

Note

To view Transact-SQL syntax for SQL Server 2014 (12.x) and earlier versions, see Previous versions documentation.

Arguments

text_of_comment
Is the character string that contains the text of the comment.

Remarks

Use two hyphens (--) for single-line or nested comments. Comments inserted with -- are terminated by a new line, which is specified with a carriage return character (U+000A), line feed character (U+000D), or a combination of the two. There is no maximum length for comments. The following table lists the keyboard shortcuts that you can use to comment or uncomment text.

Action	Standard
Make the selected text a comment	CTRL+K, CTRL+C
Uncomment the selected text	CTRL+K, CTRL+U

For more information about keyboard shortcuts, see SQL Server Management Studio Keyboard Shortcuts.

For multiline comments, see Slash Star (Block Comment) (Transact-SQL).

Examples

The following example uses the -- commenting characters.

-- Choose the AdventureWorks2022 database.  
USE AdventureWorks2022;  
GO  
-- Choose all columns and all rows from the Address table.  
SELECT *  
FROM Person.Address  
ORDER BY PostalCode ASC; -- We do not have to specify ASC because   
-- that is the default.  
GO  

See Also

Control-of-Flow Language (Transact-SQL)