On Thursday, February 19, 2015, Thomas Steinmaurer <t...@iblogmanager.com>
wrote:
> Jim,
>
> >
> http://www.cio.co.uk/insight/data-management/jim-starkeys-nosql-low-down-it-wont-solve-big-data-3598479/
>
> What do you think about "tunable consistency" instead of "eventual
> consistency"?
>
>
> http://www.datastax.com/documentation/cassandra/2.0/cassandra/dml/dml_config_consistency_c.html
>
>
I stand by my statement that any adjective used to modify "consistency" ie
equivalent to "not."
The Cassandra page seriously confuses the concepts of consistency and
durability. How can you have any form of consistency without durability?
It's completely legitimate to have settable durability (NuoDB has more
options than you can shake a stick at), but at the end of the day, a
transaction is either committed or it must appear that it never existed.
For me, consistency is dirt simple: A transaction sees a stable view of the
database but can't update a version of a record it could not see as well as
enforcement of any declared consistency constraints. A corollary is that
any and all reduced consistency modes are for the birds and exist solely
because record locking database systems cannot perform without them.
I invented MVCC to bring transactions to the masses; to make transactions
easier to use than not. All of the other crap are bandaids on systems that
essentially don't work.
I learned at DEC that most options are the product of bad design where the
designer didn't have a right answer so gave the users a choice between two
bad answers. Bah!
> Thanks,
> Thomas
>
>
> ------------------------------------------------------------------------------
> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
> from Actuate! Instantly Supercharge Your Business Reports and Dashboards
> with Interactivity, Sharing, Native Excel Exports, App Integration & more
> Get technology previously reserved for billion-dollar corporations, FREE
>
> http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk
> Firebird-Devel mailing list, web interface at
> https://lists.sourceforge.net/lists/listinfo/firebird-devel
>
--
Jim Starkey
------------------------------------------------------------------------------
Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
from Actuate! Instantly Supercharge Your Business Reports and Dashboards
with Interactivity, Sharing, Native Excel Exports, App Integration & more
Get technology previously reserved for billion-dollar corporations, FREE
http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk
Firebird-Devel mailing list, web interface at
https://lists.sourceforge.net/lists/listinfo/firebird-devel
