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https://issues.apache.org/jira/browse/HBASE-14509?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14935539#comment-14935539
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Lars Hofhansl commented on HBASE-14509:
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Bloom filters are good for point lookups, not for range scans. But BFs on
column values is a great idea!
For scans with filters we need to be able to rule out large chunks of the data.
Schema in HBase... You're talking heresy :)
> Configurable sparse indexes?
> ----------------------------
>
> Key: HBASE-14509
> URL: https://issues.apache.org/jira/browse/HBASE-14509
> Project: HBase
> Issue Type: Brainstorming
> Reporter: Lars Hofhansl
>
> This idea just popped up today and I wanted to record it for discussion:
> What if we kept sparse column indexes per region or HFile or per configurable
> range?
> I.e. For any given CQ we record the lowest and highest value for a particular
> range (HFile, Region, or a custom range like the Phoenix guide post).
> By tweaking the size of these ranges we can control the size of the index, vs
> its selectivity.
> For example if we kept it by HFile we can almost instantly decide whether we
> need scan a particular HFile at all to find a particular value in a Cell.
> We can also collect min/max values for each n MB of data, for example when we
> can the region the first time. Assuming ranges are large enough we can always
> keep the index in memory together with the region.
> Kind of a sparse local index. Might much easier than the buddy region stuff
> we've been discussing.
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