For #1, the two regions would contain roughly half the data. For #2, 1 region would not receive new data. As you see, such schema design is suboptimal.
For #3, you can split the key space evenly. Using number of region servers as number of splits is Okay. Cheers On Jul 16, 2014, at 12:25 AM, Shushant Arora <[email protected]> wrote: > Thanks! > Few more doubts > > 1.When I don't supply SPLITS at table creation , all put operation will go > to one region only. > But when region grows more than hbase.hregion.max.filesize , then 2 > regions will be created both have half-half data or another will be empty > initially? > 2.If both have 50-50% data and row key is monotonically increasing then 1 > region will be half filled always and will never be filled again ? > 3.While prespliting table only way is to specify row boundaries and key > prefixes ?Say if i don't know key ranges , as in my case its GUID > hexadecimal 32 character string , what should be region split boundary ? > and How many splits should be created - is it equal to no of regionserver > aka datanodes ? > 4.For keys of type ACTIVITYTYPE-DATE (where activity type has 2 values > 1.login 2.logout) what should be split strategy ? > > > > On Tue, Jul 15, 2014 at 7:03 PM, Ted Yu <[email protected]> wrote: > >> Shushant: >> For #2, if table has only one region, the hosting region server would >> receive all writes. >> For #4, yes - presplitting goes with fixed number of regions. >> >> Cheers >> >> >> On Tue, Jul 15, 2014 at 6:23 AM, sudhakara st <[email protected]> >> wrote: >> >>> You can find info here >>> http://hbase.apache.org/book/rowkey.design.html#rowkey.regionsplits >>> http://hortonworks.com/blog/apache-hbase-region-splitting-and-merging/ >>> >>> >>> On Tue, Jul 15, 2014 at 6:40 PM, Shushant Arora < >> [email protected] >>> wrote: >>> >>>> 1.How to split region servers at table definition time? >>>> >>>> 2.Will hbase write onto only one region server when no splits are >> defined >>>> even if key is not monotonically increasing? >>>> >>>> 3. When does a region split occurs. >>>> >>>> 4. Will no of regions be fixed when hbase table is presplitted at table >>>> creation time. >>> >>> >>> >>> -- >>> >>> Regards, >>> ...sudhakara >>
