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From "James Taylor (JIRA)" <j...@apache.org>
Subject [jira] [Comment Edited] (PHOENIX-1594) Using KeyOnlyFilter for simple query "select count(1) from <table>"
Date Sun, 18 Jan 2015 00:43:34 GMT

    [ https://issues.apache.org/jira/browse/PHOENIX-1594?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14281607#comment-14281607
] 

James Taylor edited comment on PHOENIX-1594 at 1/18/15 12:43 AM:
-----------------------------------------------------------------

Is the table a VIEW over an HBase table? Or a Phoenix TABLE?

We don't turn off caching the blocks automatically, but I think there's a JIRA for that. It's
somewhat hard to know if you should automatically not cache them. We could infer based on
the overall number of bytes from our stats now. You can always add the /*+ NO_CACHE */ hint,
though.


was (Author: jamestaylor):
Is the table a VIEW over an HBase table? Or a Phoenix TABLE?

We don't turn off caching the blocks automatically, but I think there's a JIRA for that.

> Using KeyOnlyFilter for simple query "select count(1) from <table>"
> -------------------------------------------------------------------
>
>                 Key: PHOENIX-1594
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-1594
>             Project: Phoenix
>          Issue Type: Improvement
>            Reporter: Jeffrey Zhong
>
> I found that underlying scan for query "select count(1) or count(*) from <table>"
still project all columns. 
> It should be fast if we use KeyOnlyFilter for this simple query.



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