Xp_cmdshell For OS commands

Introduced in sql server 2005
xp_cmdshall option is a server configuration option that enables system administrator.


"xp_cmdshell" is an extended stored procedure provided by Microsoft and stored
in the master database. This procedure allows you to issue operating system commands
 directly to the Windows command shell via T-SQL code


-- To allow advanced options to be changed.


EXEC sp_configure 'show advanced options', 1
GO
-- To update the currently configured value for advanced options.
RECONFIGURE
GO
-- To enable the feature.
EXEC sp_configure 'xp_cmdshell', 1
GO
-- To update the currently configured value for this feature.
RECONFIGURE
GO
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exec master.dbo.xp_cmdshell 'dir c:\temp\*.sql'
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exec master.dbo.xp_cmdshell 'mkdir "c:\temp\SQL Agent Output\new_job\"'
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DECLARE @rc int
EXEC @rc = master.dbo.xp_cmdshell 'copy c:\temp\doesnotexist.txt c:\temp\workfile.txt'
print @rc
IF @rc <> 0
BEGIN
  PRINT 'Copy Failure Skip work'
END
ELSE
BEGIN
  Print 'Copy worked now we can do some more stuff'
  ....
END
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