DECLARE @GetInstances TABLE

( Value nvarchar(100),

InstanceNames nvarchar(100),

Data nvarchar(100))

Insert into @GetInstances

EXECUTE xp_regread

@rootkey = 'HKEY_LOCAL_MACHINE',

@key = 'SOFTWARE\Microsoft\Microsoft SQL Server',

@value_name = 'InstalledInstances'

Select InstanceNames from @GetInstances