Global Variables in MS SQL Server
Global variables are pre-defined system variables. It starts with @@. It provides information about the present user environment for SQL Server. SQL Server provides multiple global variables, which are very effective to use in Transact-SQL. The following are some frequently used global variables β
- @@SERVERNAME
- @@CONNECTIONS
- @@MAX_CONNECTIONS
- @@CPU_BUSY
- @@ERROR
- @@IDLE
- @@LANGUAGE
- @@TRANCOUNT
- @@VERSION
These are explained as following below.
- @@SERVERNAME :
This is used to find the name of the machine/computer on which SQL Server is running.
Example βSelect @@servername
Output β
SERVERXX\CTRXREST
- @@CONNECTIONS :
This is used to find number of logins or attempted logins since SQL Server was last started.
Example βSelect @@connections
Output β
59846824
- @@MAX_CONNECTIONS :
This is used to find the maximum number of simultaneous connections that can be made with SQL Server or instance in this computer environment.
Example βselect @@max_connections
Output β
32767
- @@CPU_BUSY :
This is used to find the amount of time, in microseconds, that the CPU has spent doing SQL Server work since the last time SQL Server was running.
Example βSelect @@cpu_busy
Output β
887468
- @@ERROR :
This is used to check the error status (succeeded or failed) of the most recently executed statement. It contains Zero (0) if the previous transaction succeeded, else, it contains the last error number generated by the system.
Example βSelect @@error
Output β
0
- @@IDLE :
The amount of time, in microseconds, that SQL Server has been idle since it was last started.
Example βSelect @@idle
Output β
123691249
- @@LANGUAGE :
This is used to find the name of the language that is currently used by the SQL Server.
Example βSelect @@language
Output β
us_english
- @@TRANCOUNT :
This is used to count the number of open transactions in the current session.
Example βSelect @@trancount
Output β
0
- @@VERSION :
This is used to find the current version of the SQL Server Software.
Example βSelect @@version
Output β
Microsoft SQL Server 2014 (SP3-CU-GDR) (KB4535288) - 12.0.6372.1 (X64) Dec 12 2019 15:14:11 Copyright (c) Microsoft Corporation Standard Edition (64-bit) on Windows NT 6.3 <X64> (Build 9600: ) (Hypervisor)