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From you Zhuang <zhuangzixiao...@gmail.com>
Subject Re: does anyone tell me why raw measure need dictionary?
Date Thu, 01 Aug 2019 04:19:18 GMT
Thanks ShaoFeng, I have copy a rawv2 measure without dictionary instead, all memory metrics
have been around normal level since then.

> On Jul 31, 2019, at 1:16 PM, ShaoFeng Shi <shaofengshi@apache.org> wrote:
> 
> This is a limitation of the raw measure; It uses a dictionary to compress the values,
but that may make the dictionary very big. This is one of the reasons that Kylin mark the
raw measure as deprecated.
> 
> Best regards,
> 
> Shaofeng Shi 史少锋
> Apache Kylin PMC
> Email: shaofengshi@apache.org <mailto:shaofengshi@apache.org>
> 
> Apache Kylin FAQ: https://kylin.apache.org/docs/gettingstarted/faq.html <https://kylin.apache.org/docs/gettingstarted/faq.html>
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> 
> 
> 
> 
> you Zhuang <zhuangzixiaoyou@gmail.com <mailto:zhuangzixiaoyou@gmail.com>>
于2019年7月15日周一 下午11:27写道:
> I use raw measure to serve original records consults. But why does raw measure need dictionary?
 If I have a lot of raw measures, performance is slow. I see code below :
> 
> @Override
> public List<TblColRef> getColumnsNeedDictionary(FunctionDesc functionDesc) {
>     TblColRef literalCol = functionDesc.getParameter().getColRefs().get(0);
>     return Collections.singletonList(literalCol);
> }
> 
> My raw measures are always double, not big. So I don’t need dictionary at all.
> 
> I use raw measures for historical reasons, so I expect someone to tell me why and how
I can modify to use raw bytes.


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