hi 元灵， 这个是个已知bug: https://issues.apache.org/jira/browse/FLINK-17753，目前正在fix。
Bests, Godfrey 元灵 <[email protected]> 于2020年6月3日周三 下午5:39写道： > 大家好，请教个问题： > 我在pyflink中使用SQL DDL创建kafka源，如下： > kafka_source_ddl = """ > CREATE TABLE kafka_source_tb ( > name VARCHAR, > number INT, > msgtime TIMESTAMP, > WATERMARK FOR msgtime AS msgtime > ) WITH ( > 'connector.type' = 'kafka', > 'connector.version' = 'universal', > 'connector.topic' = 'mytopic', > 'connector.properties.zookeeper.connect' = 'localhost:2181', > 'connector.properties.bootstrap.servers' = 'localhost:9092', > 'format.type' = 'json', > 'format.derive-schema' = 'true' > ) > """ > st_env.sql_update(kafka_source_ddl) > > > 在使用窗口时报错，代码如下： > st_env.from_path("kafka_source_tb") \ > > .window(Slide.over("10.secends").every("1.secends").on("msgtime").alias("msgtime")) > \ > .group_by("msgtime") \ > .select("msgtime.start as b, msgtime.end as c, msgtime.rowtime > as d") \ > > > 报错如下 > : org.apache.flink.table.api.ValidationException: A group window expects a > time attribute for grouping in a stream environment. > at > org.apache.flink.table.operations.utils.factories.AggregateOperationFactory.validateStreamTimeAttribute(AggregateOperationFactory.java:293) > at > org.apache.flink.table.operations.utils.factories.AggregateOperationFactory.validateTimeAttributeType(AggregateOperationFactory.java:278) > at > org.apache.flink.table.operations.utils.factories.AggregateOperationFactory.getValidatedTimeAttribute(AggregateOperationFactory.java:271) > at > org.apache.flink.table.operations.utils.factories.AggregateOperationFactory.createResolvedWindow(AggregateOperationFactory.java:233) > at > org.apache.flink.table.operations.utils.OperationTreeBuilder.windowAggregate(OperationTreeBuilder.java:243) > at > org.apache.flink.table.api.internal.TableImpl$WindowGroupedTableImpl.select(TableImpl.java:762) > at > org.apache.flink.table.api.internal.TableImpl$WindowGroupedTableImpl.select(TableImpl.java:747) > > > 我看到有人说直接使用api的rowtime函数好像有bug，就选了用DDL的，这个error是否相关？或者是我哪里写错了？ > > > 请大家帮忙看一下 > 谢谢！ > >
