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From Aljoscha Krettek <aljos...@apache.org>
Subject Re: Expressions for Table operations (select, filter)?
Date Fri, 18 Sep 2015 15:07:40 GMT
Hi Stefan,
I added a section in the documentation that describes the syntax of the
expressions. It is a bit bare bones but I hope it helps nonetheless.

https://ci.apache.org/projects/flink/flink-docs-master/libs/table.html

Cheers,
Aljoscha

On Wed, 16 Sep 2015 at 14:55 Aljoscha Krettek <aljoscha@apache.org> wrote:

> Hi,
> unfortunately the expression syntax is not documented right now. I'm
> writing documentation right now, it should be available in a few hours.
>
> For reference, you can look at expressionDsl.scala or
> ExpressionParser.scala to see the expressions that are actually implemented.
>
> Cheers,
> Aljoscha
>
> On Wed, 16 Sep 2015 at 13:32 Stefan Winterstein <
> stefan.winterstein@dfki.de> wrote:
>
>> Where can I find a description of the expressions that can be used with
>> the Table operations, such as select() and filter()?
>>
>> I've seen the examples use code like
>>
>> > .select("word.count as count, word").filter("count = 2");
>>
>> and
>>
>> > .select("month as m, cnt.max as max")
>>
>> The Table docs
>> (https://ci.apache.org/projects/flink/flink-docs-master/libs/table.html)
>> refer to the Javadocs, but they just say "field expressions can contain
>> complex expressions and aggregations", which doesn't really help...
>>
>> And: can I reference POJO fields with these expressions?
>>
>>
>> Best,
>> -Stefan
>>
>>

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