Fabian Hueske created FLINK-8951: ------------------------------------ Summary: Support OVER windows PARTITION BY (rounded) timestamp Key: FLINK-8951 URL: https://issues.apache.org/jira/browse/FLINK-8951 Project: Flink Issue Type: New Feature Components: Table API & SQL Reporter: Fabian Hueske
There are a few interesting use cases that can be addressed by queries that follow the following pattern {code:sql} SELECT sensorId COUNT(*) OVER (PARTITION BY CEIL(rowtime TO HOUR) ORDER BY temp ROWS BETWEEN UNBOUNDED preceding AND CURRENT ROW) FROM sensors {code} Such queries can be used to compute rolling cascading (tumbling) windows with aggregates that are reset in regular intervals. This can be useful for TOP-K per minute/hour/day queries. Right now, such {{OVER}} windows are not supported, because we require that the {{ORDER BY}} clause is defined on a timestamp (time indicator) attribute. In order to support this kind of queries, we would require that the {{PARTITION BY}} clause contains a timestamp (time indicator) attribute or a function that is defined on it and which is monotonicity preserving. Once the optimizer identifies this case, it could translate the query into a special time-partitioned OVER window operator. -- This message was sent by Atlassian JIRA (v7.6.3#76005)