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Posted to user@ignite.apache.org by narges saleh <sn...@gmail.com> on 2020/02/17 11:57:59 UTC
Continuous Query Questions
Hi All,
I am getting the following streams of the following records:
name, org, year, month, day
1- john, acc, 2004, 2, 1
2- pete, rd, 2004, 3,1
3- jim,hr,2004, 5,2
4- jerry,math,2005,2,1
5- betty,park,2005,3,2
6- carry,acc,2006,1,1
I want to get notification for the first occurrence of a particular value.
So, I want to get notifications when I get records 1, 4 and 6, and in this
case, I want to get the fields, org, and year back only.
Questions:
1) Is CQ overkill in this case? If yes, what's a better alternative?
2) If not, how can I set up CQ to get only one record per occurrence?
3) How would I return only org and year back with the CQ transformer,
considering that I am working with a flat object? Note that in reality this
record has 25-30 fields (I am showing only 5 of them).
thanks.
Re: Continuous Query Questions
Posted by Evgenii Zhuravlev <e....@gmail.com>.
I'm not sure, because the final overhead depends on the object sizes. There
is a buffer for CQ, which stores 1000 entries by default, but you can
decrease it using property IGNITE_CONTINUOUS_QUERY_SERVER_BUFFER_SIZE
Evgenii
вт, 18 февр. 2020 г. в 18:09, narges saleh <sn...@gmail.com>:
> Hi Evgeni,
>
> There will be several thousands notifications/day if I have it send
> notification only when certain patterns are visited, in about 100+ caches,
> which brings up another question: wouldn't having 100+ CQs be creating too
> much overhead?
>
> thanks.
>
> On Tue, Feb 18, 2020 at 2:17 PM Evgenii Zhuravlev <
> e.zhuravlev.wk@gmail.com> wrote:
>
>> Hi,
>>
>> How many notifications do you want to get? If it's just a several
>> notifications, then you can even register separate CQ for each of the entry
>> with its own remote filters. At the same time, if you have a requirement to
>> send these notifications for a lot of entries, then this approach will
>> create a big overhead.
>>
>> Its possible to unregister a CQ after you get first notification - you
>> just need to return FALSE from a remote filter. Also, you can send not
>> exact entry, but only some fields using Transformer:
>> https://www.gridgain.com/docs/latest/developers-guide/key-value-api/continuous-queries#remote-transformer.
>> You can create some another object, which will contain only part of the
>> fields.
>>
>> Best Regards,
>> Evgeni
>>
>>
>> пн, 17 февр. 2020 г. в 03:58, narges saleh <sn...@gmail.com>:
>>
>>> Hi All,
>>> I am getting the following streams of the following records:
>>> name, org, year, month, day
>>> 1- john, acc, 2004, 2, 1
>>> 2- pete, rd, 2004, 3,1
>>> 3- jim,hr,2004, 5,2
>>> 4- jerry,math,2005,2,1
>>> 5- betty,park,2005,3,2
>>> 6- carry,acc,2006,1,1
>>>
>>> I want to get notification for the first occurrence of a particular
>>> value. So, I want to get notifications when I get records 1, 4 and 6, and
>>> in this case, I want to get the fields, org, and year back only.
>>>
>>> Questions:
>>> 1) Is CQ overkill in this case? If yes, what's a better alternative?
>>> 2) If not, how can I set up CQ to get only one record per occurrence?
>>> 3) How would I return only org and year back with the CQ transformer,
>>> considering that I am working with a flat object? Note that in reality this
>>> record has 25-30 fields (I am showing only 5 of them).
>>>
>>> thanks.
>>>
>>
Re: Continuous Query Questions
Posted by narges saleh <sn...@gmail.com>.
Hi Evgeni,
There will be several thousands notifications/day if I have it send
notification only when certain patterns are visited, in about 100+ caches,
which brings up another question: wouldn't having 100+ CQs be creating too
much overhead?
thanks.
On Tue, Feb 18, 2020 at 2:17 PM Evgenii Zhuravlev <e....@gmail.com>
wrote:
> Hi,
>
> How many notifications do you want to get? If it's just a several
> notifications, then you can even register separate CQ for each of the entry
> with its own remote filters. At the same time, if you have a requirement to
> send these notifications for a lot of entries, then this approach will
> create a big overhead.
>
> Its possible to unregister a CQ after you get first notification - you
> just need to return FALSE from a remote filter. Also, you can send not
> exact entry, but only some fields using Transformer:
> https://www.gridgain.com/docs/latest/developers-guide/key-value-api/continuous-queries#remote-transformer.
> You can create some another object, which will contain only part of the
> fields.
>
> Best Regards,
> Evgeni
>
>
> пн, 17 февр. 2020 г. в 03:58, narges saleh <sn...@gmail.com>:
>
>> Hi All,
>> I am getting the following streams of the following records:
>> name, org, year, month, day
>> 1- john, acc, 2004, 2, 1
>> 2- pete, rd, 2004, 3,1
>> 3- jim,hr,2004, 5,2
>> 4- jerry,math,2005,2,1
>> 5- betty,park,2005,3,2
>> 6- carry,acc,2006,1,1
>>
>> I want to get notification for the first occurrence of a particular
>> value. So, I want to get notifications when I get records 1, 4 and 6, and
>> in this case, I want to get the fields, org, and year back only.
>>
>> Questions:
>> 1) Is CQ overkill in this case? If yes, what's a better alternative?
>> 2) If not, how can I set up CQ to get only one record per occurrence?
>> 3) How would I return only org and year back with the CQ transformer,
>> considering that I am working with a flat object? Note that in reality this
>> record has 25-30 fields (I am showing only 5 of them).
>>
>> thanks.
>>
>
Re: Continuous Query Questions
Posted by Evgenii Zhuravlev <e....@gmail.com>.
Hi,
How many notifications do you want to get? If it's just a several
notifications, then you can even register separate CQ for each of the entry
with its own remote filters. At the same time, if you have a requirement to
send these notifications for a lot of entries, then this approach will
create a big overhead.
Its possible to unregister a CQ after you get first notification - you just
need to return FALSE from a remote filter. Also, you can send not exact
entry, but only some fields using Transformer:
https://www.gridgain.com/docs/latest/developers-guide/key-value-api/continuous-queries#remote-transformer.
You can create some another object, which will contain only part of the
fields.
Best Regards,
Evgeni
пн, 17 февр. 2020 г. в 03:58, narges saleh <sn...@gmail.com>:
> Hi All,
> I am getting the following streams of the following records:
> name, org, year, month, day
> 1- john, acc, 2004, 2, 1
> 2- pete, rd, 2004, 3,1
> 3- jim,hr,2004, 5,2
> 4- jerry,math,2005,2,1
> 5- betty,park,2005,3,2
> 6- carry,acc,2006,1,1
>
> I want to get notification for the first occurrence of a particular value.
> So, I want to get notifications when I get records 1, 4 and 6, and in this
> case, I want to get the fields, org, and year back only.
>
> Questions:
> 1) Is CQ overkill in this case? If yes, what's a better alternative?
> 2) If not, how can I set up CQ to get only one record per occurrence?
> 3) How would I return only org and year back with the CQ transformer,
> considering that I am working with a flat object? Note that in reality this
> record has 25-30 fields (I am showing only 5 of them).
>
> thanks.
>