Re: [WIP] [B-Tree] Retail IndexTuple deletion

The next version of amtargetdelete() interface and its implementation 
for nbtree, devoted to the problem of retail indextuple deletion.
Uses 'v5-0001-Make-nbtree-indexes-have-unique-keys-in-tuples' patch [1] 
to delete all logical duplicates by one tree descent.

[1] 
https://www.postgresql.org/message-id/CAH2-WzkfK=JVHjkd17TLDvsFb6psduTt5WYiT8dg+-UFc+rSSQ@mail.gmail.com

-- 
Andrey Lepikhov
Postgres Professional
https://postgrespro.com
The Russian Postgres Company