Undocumented syntax?!

• LostInEurope

  SSC Rookie

  Points: 41

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  February 6, 2008 at 6:13 am

  #69781

  Hi all,

  out of curiosity I had look at a stored procedure named sp_addumpdevice. This procedure is suggested for defining device to make backups to. The part that is 'interesting' is the line

  EXEC %%Device().NewDevice(...)

  I haven't found any syntax description for the "%%" or for the function/object/method (???) after that.

  A little further research showed that the "%%" syntax element can be found in many procedures.

  Can someone explain it?

  Thanks!

  BEGIN TRANSACTION

  -- Make sure that a device with @logicalname doesn't already exist.

  -- Always turn on the dump status bit, ignore @skip_tape (not in use)

  EXEC %%Device().NewDevice(Name = @logicalname, PhysicalName = @physicalname,

  Type = @type_enum, Size = 0)

  if @@error <> 0 -- duplicate logical name

  begin

  ROLLBACK TRANSACTION

  raiserror(15026,-1,-1,@logicalname)

  return (1)

  end

• Steve Jones - SSC Editor

  SSC Guru

  Points: 740606

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  February 6, 2008 at 8:36 am

  #775635

  I haven't seen that before and it's no used in normal querying. My guess is it's something used internally by SQL Server.

  Also, I never use dump devices. It's held over from Sybase/early SQL server.