Re: jsonb and nested hstore

On 2014-02-10 17:35:12 -0600, Merlin Moncure wrote:
> Wrong.  You still need to have code that checks the server version and
> see if it's supported (particularly for sending) and as there is *no
> protocol negotiation of the formats at present it's all going to boil
> down to if version = X do Y*.   How does the server know which
> 'versions' are ok to send? It doesn't.  Follow along with me here:
> Suppose we don't introduce a version flag today and change the format
> to some more exotic structure for 9.5.  How has the version flag made
> things easier for the client?  It hasn't. The client goes "if version
> = X do Y".

think of binary COPY outputting data in 9.4 and then trying to import
that data into 9.5. That's the interesting case here.

> What about them?  Are we now, at the
> upteenth hour of the final commit fest, suddenly deciding that binary
> wire formats going to be compatible across versions?

It has been a concern before.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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