Re: WIP: Covering + unique indexes.

> On Wed, Apr 6, 2016 at 1:50 PM, Peter Geoghegan <pg@heroku.com> wrote:
>> Personally, I like documenting assertions, and will sometimes write
>> assertions that the compiler could easily optimize away. Maybe going
>> *that* far is more a matter of personal style, but I think an
>> assertion about the new index tuple size being <= the old one is just
>> a good idea. It's not about a problem in your code at all.
>
> You should make index_truncate_tuple()/index_reform_tuple() promise to
> always do this in its comments/contract with caller as part of this,
> IMV.
>
Some notices:
- index_truncate_tuple(Relation idxrel, IndexTuple olditup, int indnatts,                       int  indnkeyatts)  Why
weneed indnatts/indnkeyatts? They are presented in idxrel struct  already
 
- follow code where index_truncate_tuple() is called, it should never called in  case where indnatts == indnkeyatts.
So,indnkeyatts should be strictly less  than indnatts, pls, change assertion. If they are equal the this function
becomescomplicated variant of CopyIndexTuple()
 
-- 
Teodor Sigaev                                   E-mail: teodor@sigaev.ru
  WWW: http://www.sigaev.ru/