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Sqoop, mail # user - incremental updates mysql to HBase


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Re: incremental updates mysql to HBase
Shengjie Min 2013-08-08, 00:47
Thanks Joanne,

so normally what's the best practice here if I were to use sqoop? For now,
I feel like just doing a brand new re-import everytime makes more sense,
but I will need to keep eyes on the performance side, what you think?

Shengjie
On 8 August 2013 00:15, Joanne Chan <[EMAIL PROTECTED]> wrote:

> 1. No
> 2. Then, you are out of luck.
>
> Sqoop isn't magic, imagine how would sqoop know what data was updated
> without any indicators?
>
>
> On Wed, Aug 7, 2013 at 12:12 PM, shengjie min <[EMAIL PROTECTED]>wrote:
>
>>
>>
>> - Add an update_time column to the source table and do the incremental
>> load by that update_time column.
>>
>> two questions to that then:
>>
>> 1. will sqoop job updates that field "update_time" automatically when it
>> runs OR my application needs to write that field?
>> 2. What if I don't wanna or I can't  touch the schema on the source table?
>>
>> THanks,
>> Shengjie
>>
>> On 8 Aug 2013, at 00:06, Joanne Chan <[EMAIL PROTECTED]> wrote:
>>
>> Add an update_time column to the source table and do the incremental load
>> by that update_time column.
>>
>>
>> On Wed, Aug 7, 2013 at 12:04 PM, shengjie min <[EMAIL PROTECTED]>wrote:
>>
>>> Hi guys,
>>>
>>> TO simplify my question, Let's say, I have a mysql table called
>>> 'student', looks like this:
>>>
>>> +----+----------+-----+
>>> | id | name     | sex |
>>> +----+----------+-----+
>>> |  1 | Alice       |   0  |
>>> |  2 | Bob         |   1  |
>>> |  3 | Charles  |   1  |
>>> +----+----------+-----+
>>>
>>> I want to import this table to HBase periodically which means I will run
>>> this sqoop job periodically. There are two goals:
>>>
>>> A.  every time there is a new record inserted to mysql table, e.g. (4,
>>> David, 1), I hope my next sqoop import will catch it and put it in HBase.
>>> B. if  there is any updates have been made to mysql rows 1, 2, 3, I want
>>> to have the updates in HBase too after next round sqoop import.
>>>
>>> I checked two types incremental updates sqoop has:  Append mode seems
>>> only satisfied goal A while Last-modified mode will require my mysql table
>>> has a timestamp column for each row(which I don't in real life). I know if
>>> I don't use incremental updates options at all, I can just get way with it
>>> by running a fresh import every time, but if my mysql table is really huge
>>> and fresh import might be a performance killer.
>>>
>>> Is there anyway I can just do incremental updates instead of having to
>>> re-run the whole import to get NEW RECORDS + UPDATES ON OLD ROWS?
>>>
>>>
>>> Shengjie
>>
>>
>>
>>
>> --
>> -- JChan
>>
>>
>>
>
>
> --
> -- JChan
>
>
--
All the best,
Shengjie Min