Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
HBase, mail # user - ways to make orders when it puts


Copy link to this message
-
Re: ways to make orders when it puts
Michael Segel 2012-10-04, 16:06
I took it that the OP wants to store the rows A1->A3 in the order in which they came in. So  It could be A3,A1,A2  as an example.
So to do this you end up prefixing the rowkey with a timestamp or something.

This is not a good idea, and I was curious as to why the order of entry was important to the OP.
On Oct 4, 2012, at 10:54 AM, Dan Han <[EMAIL PROTECTED]> wrote:

> I am not sure I hit your questoin, but if the data is not stored as what
> you expect,
> I guess it might be the problem of row key.
> As we all know, the row key is sorted in a lexicographic order in HBase.
> For example, 10 is before 9. So if your row key includes 1 ... 10,
> it is neccessory to format the single letter by adding "0".
>
> Best Wishes
> Dan Han
>
>
>
> On Thu, Oct 4, 2012 at 9:19 AM, Michael Segel <[EMAIL PROTECTED]>wrote:
>
>> Silly question. Why do you care how your data is being stored?
>>
>> Does it matter if the data is stored in rows where A1,A2, A3 are the order
>> of the keys, or
>> if its A3,A1,A2 ?
>>
>> If you say that you want to store the rows in order based on entry time,
>> you're going to also have to deal with a little nasty problem of hot
>> spotting along with your regions being only half full post spilt.
>>
>>
>> On Oct 4, 2012, at 3:54 AM, JUN YOUNG KIM <[EMAIL PROTECTED]> wrote:
>>
>>> hi, hbase users.
>>>
>>> I am wondering how we can make orders when we put under multiple threads.
>>> I mean that
>>>
>>> threads are working like this
>>>
>>> thread1 puts A1 (rowkey)
>>> thread2 puts A2
>>> thread3 puts A3
>>>
>>> by unexpected working time order,
>>> thread1 puts earlier than thread2.
>>> thread3 puts earlier than thread1.
>>>
>>> yes, I know that hbase will store it in-order like A1 -> A2 -> A3
>>>
>>> but, how could I store my datas by write-times like A3 -> A1 -> A2
>>>
>>> If I could insert timestamp value before A#, the situations I described
>> could be also happened.
>>>
>>> any ideas??
>>> (you can change row key structure if you can satisfy conditions I want
>> to archive.)
>>>
>>> thanks for your concerns.
>>>
>>>
>>
>>