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From Vasiliki Kalavri <vasilikikala...@gmail.com>
Subject Re: About flink stream table API
Date Tue, 26 Apr 2016 09:33:34 GMT
Hello,

the stream table API is currently under heavy development. So far, we
support selection, filtering, and union operations. For these operations we
use the stream SQL syntax of Apache Calcite [1]. This is as simple as
adding the "STREAM" keyword.

Registering a datastream table and running a stream SQL query works the
same way as for Datasets.
Here's a filtering example in Scala:

--------------
val env = StreamExecutionEnvironment.getExecutionEnvironment
val tEnv = TableEnvironment.getTableEnvironment(env)

val dataStream = env.addSource(...)
val t = dataStream.toTable(tEnv).as('a, 'b, 'c)
tEnv.registerTable("MyTable", t)

val sqlQuery = "SELECT STREAM * FROM MyTable WHERE a = 3"
val result = tEnv.sql(sqlQuery).toDataStream[Row]
---------------

You can find more details on our plans to support windows and aggregations
in the design document [2]. Feedback and ideas are very welcome!

Cheers,
-Vasia.

[1]: https://calcite.apache.org/docs/stream.html
[2]:
https://docs.google.com/document/d/1TLayJNOTBle_-m1rQfgA6Ouj1oYsfqRjPcp1h2TVqdI/edit?usp=sharing

On 26 April 2016 at 11:21, Zhangrucong <zhangrucong@huawei.com> wrote:

> Helloļ¼š
>
>      I want to learn the flink stream API. The stream sql is the same with
> calcite?
>
>      In the flowing link, the examples of table api are dataset, where I
> can see the detail introduction of streaming table API.
>
>
> https://ci.apache.org/projects/flink/flink-docs-master/apis/batch/libs/table.html
>
>
>
>      Thanks in advance!
>
>
>
>
>

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