Re: [Proposal] Table-level Transparent Data Encryption (TDE) and KeyManagement Service (KMS)

On Thu, Jul 25, 2019 at 03:41:05PM -0400, Stephen Frost wrote:
> Greetings,
> 
> * Bruce Momjian (bruce@momjian.us) wrote:
> > After talking to Joe Conway, I just want to mention that if we decide
> > that the LSN is unique among heap and index, or among heap or index, we
> > will need to make sure future WAL records retain this uniqueness.
> 
> One thing comes to mind regarding this and I'll admit that I don't quite
> remember exactly off-hand but I also don't want to not mention it now
> and forget to later.
> 
> What about pg_upgrade?

So, we don't carry WAL from the old cluster to the new cluster, so if
the WAL is changed and had duplicates, it would only be new WAL records.
pg_upgrade seems immune to must of this, and that is by design. 
However, I am hesitant to change the heap/index page format for
encryption because if we add fields, old pages might not fit as
encrypted pages, and then you have to move rows around, and things
become _much_ more complicated.

I don't see any other pg_upgrade issues, unless someone else does.  Oh,
we will have to check pg_control for a matching encryption format.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

+ As you are, so once was I.  As I am, so you will be. +
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