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https://issues.apache.org/jira/browse/PHOENIX-1292?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14148116#comment-14148116
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James Taylor commented on PHOENIX-1292:
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Wow, 5x slower?
|select count(\*) from x where v1 <> 1 |45s|
|select count(\*) from x where v1 = 1 |9.5s|
I don't get why it's so much slower. The latter query will often return an
empty result for regions where this value doesn't exist. Or are you saying
there are many KeyValues that have this value so that doesn't happen? Seems
like a pretty serious perf flaw in HBase. Is there something Phoenix can do to
work around this?
> Some queries that filter all rows are slow.
> -------------------------------------------
>
> Key: PHOENIX-1292
> URL: https://issues.apache.org/jira/browse/PHOENIX-1292
> Project: Phoenix
> Issue Type: Bug
> Reporter: Lars Hofhansl
>
> Sorry for the vague title.
> As mentioned PHOENIX-1281, I have seen some runtime anomalies for queries
> that should take similar amounts of time.
> 40m row tables, 4 integer column + integer key. All columns (except keys set
> to 1)
> |select distinct(v1) from x where v1 = 1 |21s|
> |select distinct(v1) from x where v1 <> 1 |50s|
> |select count(\*) from x where v1 <> 1 |45s|
> |select count(\*) from x where v1 = 1 |9.5s|
> Interestingly the queries that filter all rows are 5x slower.
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