Yes. This is very interesting approach. Is it possible to read from main key and scan from another using map/reduce? I don't want to read from single client. I use hbase version 0.94.2.21.
Thanks Oleg. On Mon, Jan 28, 2013 at 6:27 PM, Rodrigo Ribeiro < rodrigui...@jusbrasil.com.br> wrote: > In the approach that i mentioned, you would need a table to retrieve the > time of a certain event(if this information can retrieve in another way, > you may ignore this table). It would be like you posted: > event_id | time > ============= > event1 | 10:07 > event2 | 10:10 > event3 | 10:12 > event4 | 10:20 > > And a secundary table would be like: > rowkey > =========== > 10:07:event1 > 10:10:event2 > 10:12:event3 > 10:20:event4 > > That way, for your first example, you first retrieve the time of the > "event1" on the main table, and then scan starting from his position on the > secondary table("10:07:event1"), until the end of the window. > In this case(T=7) the scan will range ["10:07:event1", "10:05"). > > As Michel Segel mentioned, there is a hotspot problem on insertion using > this approach alone. > Using multiples buckets(could be a hash from the eventId) would distribute > it better, but requires to scan on all buckets from the second table to get > all events of the window of time. > > Assuming you use 3 buckets, it would look like: > rowkey > =========== > *1_*10:07:event1 > *2_*10:10:event2 > *3_*10:12:event3 > *2_*10:20:event4 > > The scans would be: ["*1*_10:07:event1", "1_10:15"), ["*2*_10:07:event1", > "2_10:15"), and ["*3*_10:07:event1", "3_10:15"), you can then combine the > results. > > Hope it helps. > > On Mon, Jan 28, 2013 at 12:49 PM, Oleg Ruchovets <oruchov...@gmail.com > >wrote: > > > Hi Rodrigo. > > Can you please explain in more details your solution.You said that I > will > > have another table. How many table will I have? Will I have 2 tables? > What > > will be the schema of the tables? > > > > I try to explain what I try to achive: > > I have ~50 million records like {time|event}. I want to put the data > in > > Hbase in such way : > > events of time X and all events what was after event X during time > > T minutes (for example during 7 minutes). > > So I will be able to scan all table and get groups like: > > > > {event1:10:02} corresponds to events {event2:10:03} , {event3:10:05} , > > {event4:10:06} > > {event2:10:30} correnponds to events {events5:10:32} , {event3:10:33} , > > {event3:10:36}. > > > > Thanks > > Oleg. > > > > > > On Mon, Jan 28, 2013 at 5:17 PM, Rodrigo Ribeiro < > > rodrigui...@jusbrasil.com.br> wrote: > > > > > You can use another table as a index, using a rowkey like > > > '{time}:{event_id}', and then scan in the range ["10:07", "10:15"). > > > > > > On Mon, Jan 28, 2013 at 10:06 AM, Oleg Ruchovets <oruchov...@gmail.com > > > >wrote: > > > > > > > Hi , > > > > > > > > I have such row data structure: > > > > > > > > event_id | time > > > > ============= > > > > event1 | 10:07 > > > > event2 | 10:10 > > > > event3 | 10:12 > > > > > > > > event4 | 10:20 > > > > event5 | 10:23 > > > > event6 | 10:25 > > > > > > > > > > > > Numbers of records is 50-100 million. > > > > > > > > > > > > Question: > > > > > > > > I need to find group of events starting form eventX and enters to the > > > time > > > > window bucket = T. > > > > > > > > > > > > For example: if T=7 munutes. > > > > Starting from event event1- {event1, event2 , event3} were detected > > > durint > > > > 7 minutes. > > > > > > > > Starting from event event2- {event2 , event3} were detected durint 7 > > > > minutes. > > > > > > > > Starting from event event4 - {event4, event5 , event6} were detected > > > during > > > > 7 minutes. > > > > Is there a way to model the data in hbase to get? > > > > > > > > Thanks > > > > > > > > > > > > > > > > -- > > > > > > *Rodrigo Pereira Ribeiro* > > > Software Developer > > > www.jusbrasil.com.br > > > > > > > > > -- > > *Rodrigo Pereira Ribeiro* > Software Developer > T (71) 3033-6371 > C (71) 8612-5847 > rodrigui...@jusbrasil.com.br > www.jusbrasil.com.br >