[Asterisk-Dev] Re: PostgreSQL support in Asterisk 1.2?

[Tilghman Lesher]

On Wednesday 10 August 2005 12:57, Kevin P. Fleming wrote:
> Tilghman Lesher wrote:
> > 	* Transactions are atomic, consistent, isolated, and durable
> > (ACID) even after system crashes and power failures.
>
> The 'C' in ACID has nothing to do with how inserted data is
> interpreted; in only applies to transactional integrity.
>
> A database that turned all inserted strings into
> 'look-what-we-did-with-your-data' could still technically be ACID
> compliant.

Only if the constraints allowed it, which is what Andrew was disputing
in MySQL, which would also make SQLite fail (since SQLite also does
not obey the constraints).

For that matter, Informix doesn't strictly follow the Isolation in ACID,
either, as uncommitted transactions may affect currently executing
queries [0].  Not being as familiar with Oracle and DB2, they might also
follow this behavior.

If we're going to be really strict with ACID, it just might be possible
that NO database actually conforms to the definition.

[0] If you delete a row in Informix, but keep the transaction open, the
row will not appear in concurrent queries, even though the transaction
may be subsequently rolled back.

-- 
Tilghman