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Fabian Hueske commented on FLINK-5624: -------------------------------------- Copying a comment from FLINK-5710. The idea is to kind of apply pattern matching for certain expressions such as {{GROUP BY FLOOR(procTime() TO HOURS)}}. The challenge is that this expression is spread across several LogicalRel nodes. The expression {{FLOOR(procTime() TO HOURS)}} will be moved into a {{LogicalProject}} (or {{LogicalCalc}}) to create a new attribute. A following {{LogicalAggregate}} will then use that attribute as a grouping column. Once we detect such a pattern, we have to rewrite the plan and replace the {{LogicalAggregate}} and parts of the {{LogicalProject}} by a {{LogicalWindowAggregate}}. The {{LogicalWindowAggregate}} includes a window definition. Depending on which marker function is used ({{rowtime}} or {{proctime}}) the window definition is either for a processing or an event time window. After the translation, the function is no longer available. With this approach, we can only translate very specific queries. However, I don't think we can easily provide a generic translation for SQL window queries. With Calcite's special window functions TUMBLE, HOP, and SESSION (see Calcite-1345 and http://calcite.apache.org/docs/stream.html) the detection of windowing patterns will be much easier. > Support tumbling window on streaming tables in the SQL API > ---------------------------------------------------------- > > Key: FLINK-5624 > URL: https://issues.apache.org/jira/browse/FLINK-5624 > Project: Flink > Issue Type: Bug > Components: Table API & SQL > Reporter: Haohui Mai > Assignee: Haohui Mai > > This is a follow up of FLINK-4691. > FLINK-4691 adds supports for group-windows for streaming tables. This jira > proposes to expose the functionality in the SQL layer via the {{GROUP BY}} > clauses, as described in > http://calcite.apache.org/docs/stream.html#tumbling-windows. -- This message was sent by Atlassian JIRA (v6.3.15#6346)