Jark wrote
> 我看你的作业里面是window agg,目前 window agg 还不支持自动拆分。1.13 的基于 window tvf 的 window
> agg支持这个参数了。可以期待下。
> 
> Best,
> Jark
> 
> On Wed, 24 Mar 2021 at 19:29, Robin Zhang <

> vincent2015qdlg@

> >
> wrote:
> 
>> Hi,guomuhua
>>       开启本地聚合,是不需要自己打散进行二次聚合的哈,建议看看官方的文档介绍。
>>
>> Best,
>> Robin
>>
>>
>> guomuhua wrote
>> > 在SQL中,如果开启了 local-global 参数:set
>> > table.optimizer.agg-phase-strategy=TWO_PHASE;
>> > 或者开启了Partial-Final 参数:set
>> table.optimizer.distinct-agg.split.enabled=true;
>> >                                          set
>> > table.optimizer.distinct-agg.split.bucket-num=1024;
>> > 还需要对应的将SQL改写为两段式吗?
>> > 例如:
>> >     原SQL:
>> >     SELECT day, COUNT(DISTINCT buy_id) as cnt FROM T GROUP BY day,
>> >
>> >     对所需DISTINCT字段buy_id模1024自动打散后,SQL:
>> >     SELECT day, SUM(cnt) total
>> >     FROM (
>> >     SELECT day, MOD(buy_id, 1024), COUNT(DISTINCT buy_id) as cnt
>> >     FROM T GROUP BY day, MOD(buy_id, 1024))
>> >     GROUP BY day
>> >
>> > 还是flink会帮我自动改写SQL,我不用关心?
>> >
>> > 另外,如果只设置开启上述参数,没有改写SQL,感觉没有优化,在flink web ui界面上也没有看到两阶段算子
>> > <
>> http://apache-flink.147419.n8.nabble.com/file/t1346/%E7%AE%97%E5%AD%90.png>
>>
>> >
>> >
>> >
>> >
>> >
>> > --
>> > Sent from: http://apache-flink.147419.n8.nabble.com/
>>
>>
>>
>>
>>
>> --
>> Sent from: http://apache-flink.147419.n8.nabble.com/
>>

感谢,如果不是window agg,开启参数后flink会自动打散是吧。那关于window agg,
不能自动打散,这部分的介绍,在文档中可以找到吗?具体在哪里呢?还是需要从源码里找呢?望指教。再次感谢



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