Hey Godfrey, in some of the use cases our users have, they have a couple of complex join queries where the key domains key evolving - we definitely want some sort of state retention for those queries; but there are other where the key domain doesn't evolve overtime, but there isn't really a guarantee on what's the maximum gap between 2 records of the same key to appear in the stream, we don't want to accidentally invalidate the state for those keys in these streams.
Because of queries with different requirements can both exist in the pipeline, I think we have to config `IDLE_STATE_RETENTION_TIME` per operator. Just wondering, has similar requirement not come up much for SQL users before? (being able to set table / query configuration inside SQL queries) We are also a little bit concerned because right now since 'toRetractStream(Table, Class, QueryConfig)' is deprecated, relying on the fact that TableConfig is read during toDataStream feels like relying on an implementation details that just happens to work, and there is no guarantee that it will keep working in the future versions... Thanks! ________________________________ From: godfrey he <godfre...@gmail.com> Sent: Monday, April 13, 2020 9:51 PM To: Jiahui Jiang <qzhzm173...@hotmail.com> Cc: Jark Wu <imj...@gmail.com>; user@flink.apache.org <user@flink.apache.org> Subject: Re: Setting different idleStateRetentionTime for different queries executed in the same TableEnvironment in Flink 1.10 Hi Jiahui, Query hint is a way for fine-grained configuration. just out of curiosity, is it a strong requirement that users need to config different IDLE_STATE_RETENTION_TIME for each operator? Best, Godfrey Jiahui Jiang <qzhzm173...@hotmail.com<mailto:qzhzm173...@hotmail.com>> 于2020年4月14日周二 上午2:07写道： Also for some more context, we are building a framework to help users build their Flink pipeline with SQL. Our framework handles all the setup and configuration, so that users only need to write the SQL queries without having to have any Flink knowledge. One issue we encountered was, for some of the streams, the key domain keeps evolving and we want to expire the states for older keys. But there is no easy ways to allow users configure their state timeout directly through SQL APIs. Currently we are asking users to configure idleStateRetentionTime in a custom SQL hint, then our framework will parse it and set it up during table registration time. An example query that users can be writing right now looks like, CREATE TABLE `/output` AS SELECT /*+ IDLE_STATE_RETENTION_TIME(minTime ='5m', maxTime ='11m') */ * FROM `/input1` a INNER JOIN `/input2` b ON a.column_name = b.column_name; Is this something Flink SQL may want to support out of the box? (Starting from Calcite 1.22.0<https://calcite.apache.org/news/2020/03/05/release-1.22.0/>, it started to provide first class hint parsing) ________________________________ From: Jiahui Jiang <qzhzm173...@hotmail.com<mailto:qzhzm173...@hotmail.com>> Sent: Sunday, April 12, 2020 4:30 PM To: Jark Wu <imj...@gmail.com<mailto:imj...@gmail.com>> Cc: user@flink.apache.org<mailto:user@flink.apache.org> <user@flink.apache.org<mailto:user@flink.apache.org>> Subject: Re: Setting different idleStateRetentionTime for different queries executed in the same TableEnvironment in Flink 1.10 Hey Jark, thank you so much for confirming! Out of curiosity, even though I agree that having too many config classes are confusing, not knowing when the config values are used during pipeline setup is also pretty confusing. For example, the name of 'TableConfig' makes me feel it's global to the whole tableEnvironment (which is true) but is only read once at execution (which is not true). Can we try to surface or add some documentation on when are these configs are read? 😄 Thank you so much! ________________________________ From: Jark Wu <imj...@gmail.com<mailto:imj...@gmail.com>> Sent: Saturday, April 11, 2020 8:45 AM To: Jiahui Jiang <qzhzm173...@hotmail.com<mailto:qzhzm173...@hotmail.com>> Cc: user@flink.apache.org<mailto:user@flink.apache.org> <user@flink.apache.org<mailto:user@flink.apache.org>> Subject: Re: Setting different idleStateRetentionTime for different queries executed in the same TableEnvironment in Flink 1.10 Yes, that's right. Set idleStateRetentionTime on TableConfig before translation should work. On Sat, 11 Apr 2020 at 14:46, Jiahui Jiang <qzhzm173...@hotmail.com<mailto:qzhzm173...@hotmail.com>> wrote: Thank you for answering! I was reading StreamExecutionEnvironmentImpl/StreamPlanner, and it seems to me that when trying to convert tables to DataStreams, planner.translate is taking the current tableConfig into account (aa in it reads the current tableConfig content even though it’s not explicitly passed in as an argument for translate). So seems like if I set tableConfig right before converting to DataStreams that should work? Or did you mean the actual tableEnvironment.execute()? Since we have a whole pipeline with multiple queries that also depends on each other. We have to have all the continuous queries executing concurrently. Thanks again! ________________________________ From: Jark Wu <imj...@gmail.com<mailto:imj...@gmail.com>> Sent: Saturday, April 11, 2020 1:24 AM To: Jiahui Jiang <qzhzm173...@hotmail.com<mailto:qzhzm173...@hotmail.com>> Cc: user@flink.apache.org<mailto:user@flink.apache.org> <user@flink.apache.org<mailto:user@flink.apache.org>> Subject: Re: Setting different idleStateRetentionTime for different queries executed in the same TableEnvironment in Flink 1.10 Hi Jiahui, QueryConfig is deprecated and will be removed in the future, because it is confusing that TableAPI has so many different config classes. If you want to set different idleStateRetentionTime for different queries, you can set a new idleStateRetentionTime on TableConfig before execute/submit the query. Best, Jark On Sat, 11 Apr 2020 at 09:21, Jiahui Jiang <qzhzm173...@hotmail.com<mailto:qzhzm173...@hotmail.com>> wrote: Just looked into the source code a bit further and realized that for StreamTableEnvironmentImpl, even for sinks it's also doing translation lazily. Any way we can have different transformation to have different queryConfig? ________________________________ From: Jiahui Jiang <qzhzm173...@hotmail.com<mailto:qzhzm173...@hotmail.com>> Sent: Friday, April 10, 2020 6:46 PM To: user@flink.apache.org<mailto:user@flink.apache.org> <user@flink.apache.org<mailto:user@flink.apache.org>> Subject: Setting different idleStateRetentionTime for different queries executed in the same TableEnvironment in Flink 1.10 Hello! I'm using Table API to write a pipeline with multiple queries. And I want to set up different idleStateRetentionTime for different queries. In Flink 1.8, it seems to be the case where I can pass in a streamQueryConfig when converting each output table into datastreams. And the translate with take the idleStateRetentionTime into account. But in Flink 1.10, that idleStateRetentionTime actually gets set on TableConfig and applies to the tableEnvironment. Is there a way to have different idleStateRetentionTime for different queries in 1.10? I saw tableEnvironment.insertInto(sink, queryConfig) still allows eager translate. But does that mean if I have multiple sinks for the same datastream with different idleStateRetentionTime(s) configuration, that will cause the transformation to be executed multiple times? Thank you!
