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Posted to user@ignite.apache.org by Latha Masters <sm...@merkleinc.com> on 2021/09/27 18:32:07 UTC
Help with ContinuousQuery issue
Hi all,
We’ve run into an issue when using ContinuousQuery and hoping someone can help provide some insight.
1 ContinuousQuery<K, V> query = new ContinuousQuery<>();
2 query.setLocalListener(listener);
3 query.setInitialQuery(new ScanQuery<>());
4 query.setPageSize(updatePageSize);
5 query.setTimeInterval(updateTimeInterval);
6 cursor = igniteCache.query(query);
7
8 for (Entry<K, V> entry : cursor) {
9 cache.put(entry.getKey(), entry.getValue());
10 }
With the code snippet above, we have verified that the igniteCache has data but occasionally the query on line 6 results in an empty cursor.
Our questions:
Is this expected behavior?
Is there some additional configuration step we are missing which could lead to inconsistent results from the initialQuery?
Is there a best practice for retrieving results from the initialQuery such as retry? We have noticed that if we retry after it fails to get results the first time, it will then succeed on a subsequent try with a one-second wait time between retries. We didn’t think this should be necessary so wondered if there was something we were doing incorrectly.
Please let me know if any additional information/logs are needed and thank you for your help!
Latha
Latha Masters
Lead Software Engineer
Office: +1 (434) 270-7713<tel:+1%20(434)%20270-7713>
Pronouns: She, Her, Hers
[Merkle Inc]<https://www.merkleinc.com/>
[LinkedIn]<https://www.linkedin.com/company/merkle/> [Twitter] <https://twitter.com/merkle> [Facebook] <https://www.facebook.com/merkleinc/> [Youtube] <https://www.youtube.com/user/MerkleCRM> [Instagram] <https://www.instagram.com/merkle/>
[cid:image507282.jpg@21231AA9.74FA36DC]
Merkle is named a Leader among Customer Database and Engagement Agencies. Get the report.<https://www2.merkleinc.com/l/47252/2021-02-09/8nlyvq>
Access Merkle’s award-winning Digital Marketing Report for the latest trends and benchmarks in digital marketing<https://www2.merkleinc.com/l/47252/2020-05-12/8g525n>
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Re: Help with ContinuousQuery issue
Posted by Latha Masters <sm...@merkleinc.com>.
Thanks for that idea – we can see that the listener works as expected, but our issue is at the beginning, when we run the initial query. At that time, it does not retrieve the data that is in the cache and we can see that because when we retry, then we get the results. This also does not happen every time, but seems to be a sporadic issue and we don’t understand why this happens.
Latha Masters
Lead Software Engineer
Office: +1 (434) 270-7713<tel:+1%20(434)%20270-7713>
Pronouns: She, Her, Hers
[Merkle Inc]<https://www.merkleinc.com/>
[LinkedIn]<https://www.linkedin.com/company/merkle/> [Twitter] <https://twitter.com/merkle> [Facebook] <https://www.facebook.com/merkleinc/> [Youtube] <https://www.youtube.com/user/MerkleCRM> [Instagram] <https://www.instagram.com/merkle/>
[cid:image761666.jpg@1343CD97.76E3E4E9]
From: Surinder Mehra <re...@gmail.com>
Date: Monday, September 27, 2021 at 2:44 PM
To: user@ignite.apache.org <us...@ignite.apache.org>
Subject: Re: Help with ContinuousQuery issue
Hi,
Did you try to print data inside local listener. As I understand it, initial query is only when cintinuous query starts, after that, local listener and remote filter (if provided) play role.
On Tue, Sep 28, 2021, 00:02 Latha Masters <sm...@merkleinc.com>> wrote:
Hi all,
We’ve run into an issue when using ContinuousQuery and hoping someone can help provide some insight.
1 ContinuousQuery<K, V> query = new ContinuousQuery<>();
2 query.setLocalListener(listener);
3 query.setInitialQuery(new ScanQuery<>());
4 query.setPageSize(updatePageSize);
5 query.setTimeInterval(updateTimeInterval);
6 cursor = igniteCache.query(query);
7
8 for (Entry<K, V> entry : cursor) {
9 cache.put(entry.getKey(), entry.getValue());
10 }
With the code snippet above, we have verified that the igniteCache has data but occasionally the query on line 6 results in an empty cursor.
Our questions:
Is this expected behavior?
Is there some additional configuration step we are missing which could lead to inconsistent results from the initialQuery?
Is there a best practice for retrieving results from the initialQuery such as retry? We have noticed that if we retry after it fails to get results the first time, it will then succeed on a subsequent try with a one-second wait time between retries. We didn’t think this should be necessary so wondered if there was something we were doing incorrectly.
Please let me know if any additional information/logs are needed and thank you for your help!
Latha
Latha Masters
Lead Software Engineer
Office:
+1 (434) 270-7713<tel:+1%20(434)%20270-7713>
Pronouns:
She, Her, Hers
[Merkle Inc]<https://www.merkleinc.com>
[LinkedIn]<https://www.linkedin.com/company/merkle>
[Twitter]<https://twitter.com/merkle>
[Facebook]<https://www.facebook.com/merkleinc>
[Youtube]<https://www.youtube.com/user/MerkleCRM>
[Instagram]<https://www.instagram.com/merkle>
[cid:image507282.jpg@21231AA9.74FA36DC]
Merkle is named a Leader among Customer Database and Engagement Agencies. Get the report.<https://www2.merkleinc.com/l/47252/2021-02-09/8nlyvq>
Access Merkle’s award-winning Digital Marketing Report for the latest trends and benchmarks in digital marketing<https://www2.merkleinc.com/l/47252/2020-05-12/8g525n>
This email and any attachments transmitted with it are intended for use by the intended recipient(s) only. If you have received this email in error, please notify the sender immediately and then delete it. If you are not the intended recipient, you must not keep, use, disclose, copy or distribute this email without the author’s prior permission. We take precautions to minimize the risk of transmitting software viruses, but we advise you to perform your own virus checks on any attachment to this message. We cannot accept liability for any loss or damage caused by software viruses. The information contained in this communication may be confidential and may be subject to the attorney-client privilege.
Merkle is named a Leader among Customer Database and Engagement Agencies. Get the report.<https://www2.merkleinc.com/l/47252/2021-02-09/8nlyvq>
Access Merkle’s award-winning Digital Marketing Report for the latest trends and benchmarks in digital marketing<https://www2.merkleinc.com/l/47252/2020-05-12/8g525n>
This email and any attachments transmitted with it are intended for use by the intended recipient(s) only. If you have received this email in error, please notify the sender immediately and then delete it. If you are not the intended recipient, you must not keep, use, disclose, copy or distribute this email without the author’s prior permission. We take precautions to minimize the risk of transmitting software viruses, but we advise you to perform your own virus checks on any attachment to this message. We cannot accept liability for any loss or damage caused by software viruses. The information contained in this communication may be confidential and may be subject to the attorney-client privilege.
Re: Help with ContinuousQuery issue
Posted by Surinder Mehra <re...@gmail.com>.
Hi,
Did you try to print data inside local listener. As I understand it,
initial query is only when cintinuous query starts, after that, local
listener and remote filter (if provided) play role.
On Tue, Sep 28, 2021, 00:02 Latha Masters <sm...@merkleinc.com> wrote:
> Hi all,
>
>
>
> We’ve run into an issue when using ContinuousQuery and hoping someone can
> help provide some insight.
>
>
>
> 1 ContinuousQuery<K, V> query = new ContinuousQuery<>();
>
> 2 query.setLocalListener(listener);
>
> 3 query.setInitialQuery(new ScanQuery<>());
>
> 4 query.setPageSize(updatePageSize);
>
> 5 query.setTimeInterval(updateTimeInterval);
>
> 6 cursor = igniteCache.query(query);
>
> 7
>
> 8 for (Entry<K, V> entry : cursor) {
>
> 9 cache.put(entry.getKey(), entry.getValue());
>
> 10 }
>
>
>
> With the code snippet above, we have verified that the igniteCache has
> data but occasionally the query on line 6 results in an empty cursor.
>
> Our questions:
>
> Is this expected behavior?
>
> Is there some additional configuration step we are missing which could
> lead to inconsistent results from the initialQuery?
>
> Is there a best practice for retrieving results from the initialQuery such
> as retry? We have noticed that if we retry after it fails to get results
> the first time, it will then succeed on a subsequent try with a one-second
> wait time between retries. We didn’t think this should be necessary so
> wondered if there was something we were doing incorrectly.
>
>
>
> Please let me know if any additional information/logs are needed and thank
> you for your help!
>
> Latha
> Latha Masters
> Lead Software Engineer
> Office: *+1 (434) 270-7713* <+1%20(434)%20270-7713>
> Pronouns: She, Her, Hers
> [image: Merkle Inc] <https://www.merkleinc.com/>
> [image: LinkedIn] <https://www.linkedin.com/company/merkle/> [image:
> Twitter] <https://twitter.com/merkle> [image: Facebook]
> <https://www.facebook.com/merkleinc/> [image: Youtube]
> <https://www.youtube.com/user/MerkleCRM> [image: Instagram]
> <https://www.instagram.com/merkle/>
>
>
>
>
>
>
>
> *Merkle is named a Leader among Customer Database and Engagement Agencies.
> Get the report.* <https://www2.merkleinc.com/l/47252/2021-02-09/8nlyvq>
>
> *Access Merkle’s award-winning Digital Marketing Report for the latest
> trends and benchmarks in digital marketing*
> <https://www2.merkleinc.com/l/47252/2020-05-12/8g525n>
>
> This email and any attachments transmitted with it are intended for use by
> the intended recipient(s) only. If you have received this email in error,
> please notify the sender immediately and then delete it. If you are not the
> intended recipient, you must not keep, use, disclose, copy or distribute
> this email without the author’s prior permission. We take precautions to
> minimize the risk of transmitting software viruses, but we advise you to
> perform your own virus checks on any attachment to this message. We cannot
> accept liability for any loss or damage caused by software viruses. The
> information contained in this communication may be confidential and may be
> subject to the attorney-client privilege.
>