Hi, Your code does not show how to create the Table of `Orders`. For how to specify the time attribute according to DDL, you can refer to the official document[1].
[1] https://ci.apache.org/projects/flink/flink-docs-release-1.11/dev/table/sql/create.html Best, Xingbo Appleyuchi <appleyu...@163.com> 于2020年12月9日周三 下午12:42写道: > my code is: > https://paste.ubuntu.com/p/gVGrj2V7ZF/ > > it complains > > A group window expects a time attribute for grouping in a stream > environment. > > but the data already as time attribute, > > How to fix it? > Thanks for your help. > > > > >