Hello, this is an interesting link. If I get one thing right, is it really true that the row-key is stored per cell? If so, I guess we have to re-think our current row-key which is combined by three fields using 48 bytes total.
Thanks, Thomas -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jean-Daniel Cryans Sent: Montag, 08. August 2011 20:26 To: [email protected] Subject: Re: import data from oracle to hbase: how much more space need to reserver? Using compression is important but so is designing the keys to be as small as possible. That means using a family name of 1 character if possible (we use "d" for "default" usually here), but also taking time to cleverly design your row keys. OpenTSDB is a good example: http://opentsdb.net/schema.html Shaving off 5 bytes of a key on 10B cells is about 46GB in savings pre-compression, but that also counts when storing that in caches, compacting, etc. J-D On Sun, Aug 7, 2011 at 8:35 PM, alex zhang <[email protected]> wrote: > it's depend on the orginal column number in oracle, and the data > length in the oracle. > the key in hbase include each row key+column name+timestape+TTL. so if > you have many column and the actually column value is very small, then > you the hbase table is much bigger then table in oracle. > So be sure use compress in hbase. > > I had a test table in oracle is 3G, after import to hbase, it's 28G. > with gz compress it about 4G, with lzo compress it's about 7G. > > Thanks > Zhang, Gui > > 2011/8/6 Daniel,Wu <[email protected]> > >> if a table in oracle has a size of 100T, and then put it into hbase, >> how much space normally will hbase take? >> >
