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Posted to user@flink.apache.org by Flavio Pompermaier <po...@okkam.it> on 2019/07/01 13:26:38 UTC
Re: LookupableTableSource question
I probably messed up with the meaning of eval()..thus it is called once for
every distinct key (that could be composed by a combination of fields)?
So, the other question is..how do I enable Blink planner support?
Since when is LATERAL TABLE available in Flink? Is it equivalent to using
temporal tables [1]?
[1]
https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/streaming/temporal_tables.html
Best,
Flavio
On Sat, Jun 29, 2019 at 3:16 AM JingsongLee <lz...@aliyun.com> wrote:
> The keys means joint primary keys, it is not list of keys, in your case,
> maybe there is a single key?
>
> Best, Jingsong Lee
>
>
> 来自阿里邮箱 iPhone版
> <https://itunes.apple.com/us/app/a-li-yun-you/id923828102?l=zh&ls=1&mt=8>
>
> ------------------Original Mail ------------------
> *From:*Flavio Pompermaier <po...@okkam.it>
> *Date:*2019-06-28 22:53:31
> *Recipient:*JingsongLee <lz...@aliyun.com>
> *CC:*user <us...@flink.apache.org>
> *Subject:*Re: LookupableTableSource question
> Sorry I copied and pasted twice the current eval method...I'd do this:
>
> public void eval(Object... keys) {
> for (Object kkk : keys) {
> Row keyRow = Row.of(kkk);
> if (cache != null) {
> List<Row> cachedRows = cache.getIfPresent(keyRow);
> if (cachedRows != null) {
> for (Row cachedRow : cachedRows) {
> collect(cachedRow);
> }
> return;
> }
> }
> }
> ...
>
> On Fri, Jun 28, 2019 at 4:51 PM Flavio Pompermaier <po...@okkam.it>
> wrote:
>
>> This could be a good fit, I'll try to dig into it and see if it can be
>> adapted to a REST service.
>> The only strange thing I see is that the key of the local cache is per
>> block of keys..am I wrong?
>> Shouldn't it cycle over the list of passed keys?
>>
>> Right now it's the following:
>>
>> Cache<Row, List<Row>> cache;
>>
>> public void eval(Object... keys) {
>> Row keyRow = Row.of(keys);
>> if (cache != null) {
>> List<Row> cachedRows = cache.getIfPresent(keyRow);
>> if (cachedRows != null) {
>> for (Row cachedRow : cachedRows) {
>> collect(cachedRow);
>> }
>> return;
>> }
>> }
>> ...
>>
>> while I'd use the following (also for JDBC):
>>
>> Cache<Row, List<Row>> cache;
>>
>> public void eval(Object... keys) {
>> Row keyRow = Row.of(keys);
>> if (cache != null) {
>> List<Row> cachedRows = cache.getIfPresent(keyRow);
>> if (cachedRows != null) {
>> for (Row cachedRow : cachedRows) {
>> collect(cachedRow);
>> }
>> return;
>> }
>> }
>> ...
>>
>> public void eval(Object... keys) {
>> for (Object kkk : keys) {
>> Row keyRow = Row.of(kkk);
>> if (cache != null) {
>> List<Row> cachedRows = cache.getIfPresent(keyRow);
>> if (cachedRows != null) {
>> for (Row cachedRow : cachedRows) {
>> collect(cachedRow);
>> }
>> return;
>> }
>> }
>> }
>> ...
>>
>> Am I missing something?
>>
>>
>> On Fri, Jun 28, 2019 at 4:18 PM JingsongLee <lz...@aliyun.com>
>> wrote:
>>
>>> Hi Flavio:
>>>
>>> I just implement a JDBCLookupFunction[1]. You can use it as table
>>> function[2]. Or use
>>> blink temporal table join[3] (Need blink planner support).
>>> I add a google guava cache in JDBCLookupFunction with configurable
>>> cacheMaxSize
>>> (avoid memory OOM) and cacheExpireMs(For the fresh of lookup table).
>>> Is that you want?
>>>
>>> [1]
>>> https://github.com/JingsongLi/flink/blob/cc80999279b38627b37fa7550fb6610eee450d86/flink-connectors/flink-jdbc/src/main/java/org/apache/flink/api/java/io/jdbc/JDBCLookupFunction.java
>>> [2]
>>> https://github.com/JingsongLi/flink/blob/cc80999279b38627b37fa7550fb6610eee450d86/flink-connectors/flink-jdbc/src/test/java/org/apache/flink/api/java/io/jdbc/JDBCLookupFunctionITCase.java#L143
>>> [3]
>>> https://github.com/apache/flink/blob/master/flink-table/flink-table-planner-blink/src/test/scala/org/apache/flink/table/runtime/stream/sql/LookupJoinITCase.scala#L75
>>>
>>> Best, JingsongLee
>>>
>>> ------------------------------------------------------------------
>>> From:Flavio Pompermaier <po...@okkam.it>
>>> Send Time:2019年6月28日(星期五) 21:04
>>> To:user <us...@flink.apache.org>
>>> Subject:LookupableTableSource question
>>>
>>> Hi to all,
>>> I have a use case where I'd like to enrich a stream using a rarely
>>> updated lookup table.
>>> Basically, I'd like to be able to set a refresh policy that is triggered
>>> either when a key was not found (a new key has probably been added in the
>>> mean time) or a configurable refresh-period has elapsed.
>>>
>>> Is there any suggested solution to this? The LookupableTableSource looks
>>> very similar to what I'd like to achieve but I can't find a real-world
>>> example using it and it lacks of such 2 requirements (key-values are not
>>> refreshed after a configurable timeout and a KeyNotFound callback cannot be
>>> handled).
>>>
>>> Any help is appreciated,
>>> Flavio
>>>
>>>
>>>
>>
>
Re: LookupableTableSource question
Posted by JingsongLee <lz...@aliyun.com>.
> how do I enable Blink planner support?
After flink-1.9 release, you can try Blink-planner.
>Since when is LATERAL TABLE available in Flink? Is it equivalent to using temporal tables?
LATERAL TABLE is table function in table, it is available in Flink for a long time.[1]
It is different from temporal table.
[1] https://ci.apache.org/projects/flink/flink-docs-release-1.8/dev/table/udfs.html#table-functions
Best, JingsongLee
------------------------------------------------------------------
From:Flavio Pompermaier <po...@okkam.it>
Send Time:2019年7月1日(星期一) 21:26
To:JingsongLee <lz...@aliyun.com>
Cc:user <us...@flink.apache.org>
Subject:Re: LookupableTableSource question
I probably messed up with the meaning of eval()..thus it is called once for every distinct key (that could be composed by a combination of fields)?
So, the other question is..how do I enable Blink planner support?
Since when is LATERAL TABLE available in Flink? Is it equivalent to using temporal tables [1]?
[1] https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/streaming/temporal_tables.html
Best,
Flavio
On Sat, Jun 29, 2019 at 3:16 AM JingsongLee <lz...@aliyun.com> wrote:
The keys means joint primary keys, it is not list of keys, in your case, maybe there is a single key?
Best, Jingsong Lee
来自阿里邮箱 iPhone版
------------------Original Mail ------------------
From:Flavio Pompermaier <po...@okkam.it>
Date:2019-06-28 22:53:31
Recipient:JingsongLee <lz...@aliyun.com>
CC:user <us...@flink.apache.org>
Subject:Re: LookupableTableSource question
Sorry I copied and pasted twice the current eval method...I'd do this:
public void eval(Object... keys) {
for (Object kkk : keys) {
Row keyRow = Row.of(kkk);
if (cache != null) {
List<Row> cachedRows = cache.getIfPresent(keyRow);
if (cachedRows != null) {
for (Row cachedRow : cachedRows) {
collect(cachedRow);
}
return;
}
}
}
...
On Fri, Jun 28, 2019 at 4:51 PM Flavio Pompermaier <po...@okkam.it> wrote:
This could be a good fit, I'll try to dig into it and see if it can be adapted to a REST service.
The only strange thing I see is that the key of the local cache is per block of keys..am I wrong?
Shouldn't it cycle over the list of passed keys?
Right now it's the following:
Cache<Row, List<Row>> cache;
public void eval(Object... keys) {
Row keyRow = Row.of(keys);
if (cache != null) {
List<Row> cachedRows = cache.getIfPresent(keyRow);
if (cachedRows != null) {
for (Row cachedRow : cachedRows) {
collect(cachedRow);
}
return;
}
}
...
while I'd use the following (also for JDBC):
Cache<Row, List<Row>> cache;
public void eval(Object... keys) {
Row keyRow = Row.of(keys);
if (cache != null) {
List<Row> cachedRows = cache.getIfPresent(keyRow);
if (cachedRows != null) {
for (Row cachedRow : cachedRows) {
collect(cachedRow);
}
return;
}
}
...
public void eval(Object... keys) {
for (Object kkk : keys) {
Row keyRow = Row.of(kkk);
if (cache != null) {
List<Row> cachedRows = cache.getIfPresent(keyRow);
if (cachedRows != null) {
for (Row cachedRow : cachedRows) {
collect(cachedRow);
}
return;
}
}
}
...
Am I missing something?
On Fri, Jun 28, 2019 at 4:18 PM JingsongLee <lz...@aliyun.com> wrote:
Hi Flavio:
I just implement a JDBCLookupFunction[1]. You can use it as table function[2]. Or use
blink temporal table join[3] (Need blink planner support).
I add a google guava cache in JDBCLookupFunction with configurable cacheMaxSize
(avoid memory OOM) and cacheExpireMs(For the fresh of lookup table).
Is that you want?
[1] https://github.com/JingsongLi/flink/blob/cc80999279b38627b37fa7550fb6610eee450d86/flink-connectors/flink-jdbc/src/main/java/org/apache/flink/api/java/io/jdbc/JDBCLookupFunction.java
[2] https://github.com/JingsongLi/flink/blob/cc80999279b38627b37fa7550fb6610eee450d86/flink-connectors/flink-jdbc/src/test/java/org/apache/flink/api/java/io/jdbc/JDBCLookupFunctionITCase.java#L143
[3] https://github.com/apache/flink/blob/master/flink-table/flink-table-planner-blink/src/test/scala/org/apache/flink/table/runtime/stream/sql/LookupJoinITCase.scala#L75
Best, JingsongLee
------------------------------------------------------------------
From:Flavio Pompermaier <po...@okkam.it>
Send Time:2019年6月28日(星期五) 21:04
To:user <us...@flink.apache.org>
Subject:LookupableTableSource question
Hi to all,
I have a use case where I'd like to enrich a stream using a rarely updated lookup table.
Basically, I'd like to be able to set a refresh policy that is triggered either when a key was not found (a new key has probably been added in the mean time) or a configurable refresh-period has elapsed.
Is there any suggested solution to this? The LookupableTableSource looks very similar to what I'd like to achieve but I can't find a real-world example using it and it lacks of such 2 requirements (key-values are not refreshed after a configurable timeout and a KeyNotFound callback cannot be handled).
Any help is appreciated,
Flavio