Thank you all.
2011/1/27 Matt Corgan <[email protected]> > The full row name, column family name, and column qualifier are stored with > every cell (called a KeyValue). Using gzip or lzo compression can greatly > reduce the size of the data stored on disk, and prefix compression could > eventually reduce the size of the data stored in memory. > > But, to your question about performance, most get/scan operations require > iterating through and comparing the byte arrays that back the KeyValues, so > the more bytes it has to iterate over, the slower it will be. However, > we're talking about sequential memory access which computers are very good > at, so what *overall *performance increase you can expect from shortening > the values is hard to say. > > > On Wed, Jan 26, 2011 at 12:54 PM, Bill Graham <[email protected]> > wrote: > > > I can't say from experience, but here's a thread that implies that > > shorter column names are better. > > > > http://search-hadoop.com/m/oWZQd161GI22 > > > > On Tue, Jan 25, 2011 at 11:14 PM, JinChao Wen <[email protected]> > > wrote: > > > Hi all, > > > > > > If there are lots of very long column family name and column name in > my > > > table, is there any performance impact on query? > > > > > > thx. > > > > > > > > > JinChao > > > > > >
