APP_NAME (Transact-SQL)
Applies to: 
SQL Server
Azure SQL Database
Azure SQL Managed Instance
This function returns the application name for the current session, if the application sets that name value.
Important
The client provides the application name, and APP_NAME does not verify the application name value in any way. Do not use APP_NAME as part of a security check.
Transact-SQL syntax conventions
Syntax
APP_NAME ( )
Return Types
nvarchar(128)
Remarks
Use APP_NAME to distinguish between different applications, as a way to perform different actions for those applications. For example, APP_NAME can distinguish between different applications, which allows for a different date format for each application. It can also allow for the return of an informational message to certain applications.
To set an application name in Management Studio, click Options in the Connect to Database Engine dialog box. On the Additional Connection Parameters tab, provide an app attribute in the format ;app='application_name'
Example
This example checks whether the client application that initiated this process is a SQL Server Management Studio session. It then provides a date value in either US or ANSI format.
USE AdventureWorks2022;
GO
IF APP_NAME() = 'Microsoft SQL Server Management Studio - Query'
PRINT 'This process was started by ' + APP_NAME() + '. The date is ' + CONVERT ( VARCHAR(100) , GETDATE(), 101) + '.';
ELSE
PRINT 'This process was started by ' + APP_NAME() + '. The date is ' + CONVERT ( VARCHAR(100) , GETDATE(), 102) + '.';
GO