Horton

RE: Revisited: Transactions, insert unique.

Peter Eisentraut <e99re41@docs.uu.se>

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From: Peter Eisentraut <e99re41@DoCS.UU.SE>
To: Hiroshi Inoue <Inoue@tpf.co.jp>
Cc: Ed Loehr <eloehr@austin.rr.com>, Joachim Achtzehnter <joachim@kraut.bc.ca>, pgsql-general@postgresql.org, Tom Lane <tgl@sss.pgh.pa.us>
Date: 2000-04-27T07:45:32Z
Lists: pgsql-general 
On Thu, 27 Apr 2000, Hiroshi Inoue wrote:

> PostgreSQL's SERIALIZABLE isolation level would allow both inserts.
> READ COMMITED isolation level wouldn't allow A's inserts.
> 
> As I mentioned in another posting,PostgreSQL's SERIALIZABLE
> isolation level isn't completely serializable and it's same as Oracle.
> Probably Vadim refers to this incomplete serializability somewhere
> in documentation.
> It seems almost impossible to implement complete serializability
> under MVCC without using table level locking. I love MVCC much
> more than theoretically beautiful complete serializability.

Given that Postgres correctly recognizes concurrent updates and aborts one
of the transactions, how difficult would it be to do the same for inserts?

-- 
Peter Eisentraut                  Sernanders väg 10:115
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