Re: [HACKERS] proposal: session server side variables

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 COULD YOU REMOVE THE PARTS OF EMAILS YOU ARE NOT RESPONDING TO WHEN
 REPLYING IN THE THREAD?
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Hmmm. It seems that you can't. You should, really.

If you use patterns that I wrote - the security context will be valid always.

No: This pattern assumes that operations started in the "TRY" zone cannot fail later on... This assumption is false because of possible deferred triggers for instance. See attached example:

ok .. it is pretty artificial, but ok.

Good. We seem to agree that some kind of transactional support is needed for the use case, which is pretty logical.

In this case the reset to NULL on ROLLBACK should be enough.

Probably.

So I expect that you are going to update your proposal somehow to provide some transactional properties.

Note that if you have some mecanism for doing a NULL on rollback, then why not just keep and reset the previous value if needed? This just means that you have a transactional variable, which is fine from my point of view. As I already wrote, session variable are memory only, so transactional does not involve costs such as WAL.

Also note that user-defined GUCs already implements the transactional property, so probably the mecanism is already available and can be reused.

--
Fabien.