Hi Taras ~ There is a look up cache for temporal join but it default is false, see [1]. That means, by default FLINK SQL would lookup the external databases on each record from the JOIN LHS.
Did you use the temporal table join syntax or normal stream-stream join syntax ? The temporal table join uses the SYSTEM_TIME AS OF keywords, see [2] [1] https://ci.apache.org/projects/flink/flink-docs-master/dev/table/connectors/jdbc.html#lookup-cache [2] https://ci.apache.org/projects/flink/flink-docs-master/dev/table/sql/queries.html#joins Taras Moisiuk <[email protected]> 于2020年12月27日周日 上午3:13写道： > Hi everyone! > I'm using Flink 1.12.0 with SQL API. > > I'm developing a streaming job with join and insertion into postgreSQL. > There is two tables in join: > 1. Dynamic table based on kafka topic > 2. Small lookup JDBC table > > From what I can see Flink job reads data from JDBC table only on startup > and > mark task as FINISHED. > Does it mean that Flink misses all updates from this table and join > reflects > only table state on startup? > > And the other question is, how to enable checkpointing for this job? I know > that checkpointing for jobs with finished tasks is not supported now, but > maybe I can keep such tasks in RUNNING state? > > Thank you! > > > > -- > Sent from: > http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/ >
