I see. As mentioned, Flink uses Dynamic Tables, which are a logical concept. They don't necessarily (fully) materialize during query execution.
On Tue, Sep 27, 2022 at 1:35 PM <pod...@gmx.com> wrote: > > I was thinking if I can use Flink to process large files and save result > to another file or database (jdbc). > So loading file into Flink table and then loop through rows inserting > result to some temp Flink table. > Then save result to jdbc table or file. > > > > Sent: Thursday, September 22, 2022 at 5:06 PM > From: "Martijn Visser" <martijnvis...@apache.org> > To: "Xuyang" <xyzhong...@163.com> > Cc: pod...@gmx.com, user@flink.apache.org > Subject: Re: Re: INSERT INTO will work faster in Flink than in regular > database? > > Hi, > > What is your use case? Flink doesn't have an UPDATE statement, because > Flink relies on Dynamic Tables and Continuous Queries. [1] > > Best regards, > > Martijn > > [1] > https://nightlies.apache.org/flink/flink-docs-stable/docs/dev/table/concepts/dynamic_tables/ > > > On Wed, Sep 21, 2022 at 5:40 PM Xuyang <xyzhong...@163.com[mailto: > xyzhong...@163.com]> wrote: > Hi, You're right, there's no keyword 'update' in flink. > > > > > > -- > > Best！ > Xuyang > > > > 在 2022-09-21 22:40:03，pod...@gmx.com[mailto:pod...@gmx.com] 写道： > > Thank you - I'll try. > There is no 'UPDATE' clause in Flink SQL? > > > > Sent: Monday, September 19, 2022 at 4:09 AM > From: "Shengkai Fang" <fskm...@gmail.com[mailto:fskm...@gmail.com]> > To: pod...@gmx.com[mailto:pod...@gmx.com] > Cc: user@flink.apache.org[mailto:user@flink.apache.org] > Subject: Re: INSERT INTO will work faster in Flink than in regular > database? > > Hi. I think you can write a udf[1] to process some fields and then insert > into the sink. > > Best. > Shengkai > > [1] > https://nightlies.apache.org/flink/flink-docs-master/docs/dev/table/functions/udfs/[https://nightlies.apache.org/flink/flink-docs-master/docs/dev/table/functions/udfs/] > > > <pod...@gmx.com[mailto:pod...@gmx.com]> 于2022年9月15日周四 22:10写道：What's the > most effective way (performance) to update big no of rows? > Sure this will be probably "INSERT INTO table (column1) SELECT column1 > FROM ...". Anyway, I do not see any "UPDATE" in Flink? > But sometimes SQL is not enough. > Suppose I have code: > > TableResult tableResult1 = tEnv.executeSql("SELECT * FROM SomeTable"); > try (org.apache.flink.util.CloseableIterator<Row> it = > tableResult1.collect()) { > while(it.hasNext()) { > Row row = it.next(); > //Treat row: > String x_field = row.getField("some_column").toString(); > //Do something with x_field > ... > tEnv.executeSql("INSERT INTO AnotherTable (column) VALUES > ('new_value')"); > } > } > > But this INSERT will be probably performance killer... > > Any suggestion how to do it in a smart way? > > Mike >
