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USER_NAME (Transact-SQL)

  • Стаття

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

Returns a database user name from a specified identification number, or the current user name.

Transact-SQL syntax conventions

Syntax

USER_NAME ( [ ID ] )

Arguments

ID

The identification number associated with a database user, as listed in sys.database_principals. ID is int. The parentheses are required.

Return types

nvarchar(128)

Remarks

When ID is omitted, the current user in the current context is assumed. If the parameter contains the word NULL, USER_NAME will return NULL. When USER_NAME is called without specifying an ID after an EXECUTE AS statement, USER_NAME returns the name of the impersonated user. If a Windows principal accesses the database by way of membership in a group, USER_NAME returns the name of the Windows principal instead of the group.

Although the USER_NAME() function is supported on Azure SQL Database, using EXECUTE AS USER = USER_NAME(n) is not supported on Azure SQL Database.

Examples

A. Use USER_NAME() to identify a user ID

The following example returns the user name for user ID 13, as listed in sys.database_principals.

SELECT USER_NAME(13);  
GO

B. Use USER_NAME without an ID

The following example finds the name of the current user without specifying an ID.

SELECT USER_NAME();  
GO

Here is the result set for a user that is a member of the sysadmin fixed server role.

dbo

C. Use USER_NAME in the WHERE clause

The following example finds the row in sys.database_principals, in which the name is equal to the result of applying the system function USER_NAME to user identification number 1.

SELECT name FROM sys.database_principals WHERE name = USER_NAME(1);  
GO

Here's the result set.

name  
------------------------------  
dbo  
  
(1 row(s) affected)

D. Call USER_NAME during impersonation with EXECUTE AS

The following example shows how USER_NAME behaves during impersonation.

EXECUTE AS is not currently supported on Microsoft Fabric.

Caution

When testing with EXECUTE AS, always script a REVERT to follow.

SELECT USER_NAME();  
GO  
EXECUTE AS USER = 'Zelig';  
GO  
SELECT USER_NAME();  
GO  
REVERT;  
GO  
SELECT USER_NAME();  
GO

Here's the result set.

-------------
dbo  

-------------
Zelig  

-------------
dbo

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

E. Use USER_NAME without an ID

The following example finds the name of the current user without specifying an ID.

SELECT USER_NAME();

Here is the result set for a currently logged-in user.

User7

F. Use USER_NAME in the WHERE clause

The following example finds the row in sysusers in which the name is equal to the result of applying the system function USER_NAME to user identification number 1.

SELECT name FROM sysusers WHERE name = USER_NAME(1);

Here's the result set.

name                             
------------------------------   
User7

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