Re: Compressed TOAST Slicing

On 3/13/19 3:19 AM, Michael Paquier wrote:
> On Tue, Mar 12, 2019 at 07:01:17PM -0700, Andres Freund wrote:
>> I don't think this is even close to popular enough to incur the
>> maybe of a separate function / more complicated interface. By this
>> logic we can change basically no APIs anymore. 
> 
> Well, if folks here think that it is not worth worrying about, I won't
> cry on that either.  If only the original API is kept, could it just
> be possible to make it extensible with some bits16 flags then?  Adding
> only a boolean is not really appealing.

In my experience "extensible" APIs with bitmasks are terrible - it's a
PITA to both use them and maintain stuff that calls them. That is not to
say there is no use for that design pattern, or that I like API breaks.
But I very much prefer when an API change breaks things, alerting me of
places that may require attention.

And I'm with Andres here about the complexity being rather unwarranted
here - I don't think we've changed pglz API in years (if ever), so what
is the chance we'd actually benefit from the extensibility soon?

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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