This question fairly common on the list, for example: http://search-hadoop.com/m/jusKg172GBC/timestamp+hash++key/v=threaded
-chris On Mar 20, 2011, at 12:16 PM, Niels Nuyttens wrote: > Hi guys, > > this is an interesting discussion, please excuse me for hijacking it and > posing an examplatory problem: > > suppose one is getting data from monitoring devices. A composite key > could be made using <date>_<monitoring_type>. Would this lead to > hotspots? Could hashing then solve this problem, and won't I lose the > advantage of being able to list my monitoring data chronologically? > > Thanks in advance, > > Niels > > > On Sun, 2011-03-20 at 11:57 -0700, Chris Tarnas wrote: >> There is none - HBase uses a total order partitioner. The straight key value >> itself determines which region a row is put into. This allows for very rapid >> scans of sequential data, among other things but does mean it is easier to >> hotspot regions. Key design is very important. >> >> -chris >> >> On Mar 20, 2011, at 11:41 AM, Lior Schachter wrote: >> >>> the hash function that distributes the rows between the regions. >>> >>> On Sun, Mar 20, 2011 at 8:36 PM, Stack <st...@duboce.net> wrote: >>> >>>> Hash? Which hash are you referring to sir? >>>> St.Ack >>>> >>>> On Sun, Mar 20, 2011 at 10:06 AM, Lior Schachter <li...@infolinks.com> >>>> wrote: >>>>> Hi, >>>>> What is the API or configuration for changing the default hash function >>>> for >>>>> a specific htable. >>>>> >>>>> thanks, >>>>> Lior >>>>> >>>> >> > >
