yes thanks for the clarification. But why would I ever have MV with the same partition key? if it is the same partition key I could just read from the base table right? our MV Partition key contains the columns from the base table partition key but in a different order plus an additional column (which is allowed as of today)
On Fri, Feb 10, 2017 at 10:23 AM, Benjamin Roth <benjamin.r...@jaumo.com> wrote: > It depends on your model. > If the base table + MV have the same partition key, then the MV mutations > are applied synchronously, so they are written as soon the write request > returns. > => In this case you can rely on the R+F > RF > > If the partition key of the MV is different, the partition of the MV is > probably placed on a different host (or said differently it cannot be > guaranteed that it is on the same host). In this case, the MV updates are > executed async in a logged batch. So it can be guaranteed they will be > applied eventually but not at the time the write request returns. > => You cannot rely and there is no possibility to absolutely guarantee > anything, not matter what CL you choose. A MV update may always "arrive > late". I guess it has been implemented like this to not block in case of > remote request to prefer the cluster sanity over consistency. > > Is it now 100% clear? > > 2017-02-10 19:17 GMT+01:00 Kant Kodali <k...@peernova.com>: > > > So R+W > RF doesnt apply for reads on MV right because say I set QUORUM > > level consistency for both reads and writes then there can be a scenario > > where a write is successful to the base table and then say immediately I > do > > a read through MV but prior to MV getting the update from the base table. > > so there isn't any way to make sure to read after MV had been > successfully > > updated. is that correct? > > > > On Fri, Feb 10, 2017 at 6:30 AM, Benjamin Roth <benjamin.r...@jaumo.com> > > wrote: > > > > > Hi Kant > > > > > > Is it clear now? > > > Sorry for the confusion! > > > > > > Have a nice one > > > > > > Am 10.02.2017 09:17 schrieb "Kant Kodali" <k...@peernova.com>: > > > > > > thanks! > > > > > > On Thu, Feb 9, 2017 at 8:51 PM, Benjamin Roth <benjamin.r...@jaumo.com > > > > > wrote: > > > > > > > Yes it is > > > > > > > > Am 10.02.2017 00:46 schrieb "Kant Kodali" <k...@peernova.com>: > > > > > > > > > If reading from materialized view with a consistency level of > quorum > > am > > > I > > > > > guaranteed to have the most recent view? other words is w + r > n > > > > contract > > > > > maintained for MV's as well for both reads and writes? > > > > > > > > > > Thanks! > > > > > > > > > > > > > > > > > > -- > Benjamin Roth > Prokurist > > Jaumo GmbH · www.jaumo.com > Wehrstraße 46 · 73035 Göppingen · Germany > Phone +49 7161 304880-6 · Fax +49 7161 304880-1 > AG Ulm · HRB 731058 · Managing Director: Jens Kammerer >
