declare @uu uniqueidentifier = 'C50B0567-F8CC-4219-A1E1-91C97BD9AE1B'
select @uu
declare @zaza bigint = ( select convert(bigint, convert (varbinary(8), @uu, 1)) )
select @zaza
select CONVERT( uniqueidentifier , convert( varbinary(16) , @zaza , 1 ) )
declare @uu uniqueidentifier = 'C50B0567-F8CC-