---
title: "SUSER_NAME (Transact-SQL) | Microsoft Docs"
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ms.date: "03/14/2017"
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  - "SUSER_NAME"
  - "SUSER_NAME_TSQL"
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helpviewer_keywords: 
  - "security identification names [SQL Server]"
  - "logins [SQL Server], users"
  - "identification names for logins [SQL Server]"
  - "users [SQL Server], logins"
  - "SUSER_NAME function"
  - "logins [SQL Server], names"
  - "names [SQL Server], logins"
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---
# SUSER_NAME (Transact-SQL)
[!INCLUDE[tsql-appliesto-ss2008-xxxx-asdw-xxx_md](../../includes/tsql-appliesto-ss2008-xxxx-asdw-xxx-md.md)]

  Returns the login identification name of the user.  
  
 ![Topic link icon](../../database-engine/configure-windows/media/topic-link.gif "Topic link icon") [Transact-SQL Syntax Conventions](../../t-sql/language-elements/transact-sql-syntax-conventions-transact-sql.md)  
  
## Syntax  
  
```  
  
SUSER_NAME ( [ server_user_id ] )   
```  
  
## Arguments  
 *server_user_id*  
 Is the login identification number of the user. *server_user_id*, which is optional, is **int**. *server_user_id* can be the login identification number of any [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] login or [!INCLUDE[msCoName](../../includes/msconame-md.md)] Windows user or group that has permission to connect to an instance of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)]. If *server_user_id* is not specified, the login identification name for the current user is returned. If the parameter contains the word NULL will return NULL.  
  
## Return Types  
 **nvarchar(128)**  
  
## Remarks  
 In [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] version 7.0, the security identification number (SID) replaced the server user identification number (SUID).  
  
 SUSER_NAME returns a login name only for a login that has an entry in the **syslogins** system table.  
  
 SUSER_NAME can be used in a select list, in a WHERE clause, and anywhere an expression is allowed, and must always be followed by parentheses, even if no parameter is specified.  
  
## Examples  
 The following example returns the login identification name of the user with a login identification number of `1`.  
  
```  
SELECT SUSER_NAME(1);  
```  
  
## See Also  
 [SUSER_ID (Transact-SQL)](../../t-sql/functions/suser-id-transact-sql.md)   
 [Principals (Database Engine)](../../relational-databases/security/authentication-access/principals-database-engine.md)