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From "Kannan Muthukkaruppan (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (HBASE-5032) Add other DELETE type information into the delete bloom filter to optimize the time range query
Date Wed, 17 Oct 2012 03:28:03 GMT

     [ https://issues.apache.org/jira/browse/HBASE-5032?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Kannan Muthukkaruppan updated HBASE-5032:
-----------------------------------------

    Description: 
To speed up time range scans we need to seek to the maximum timestamp of the requested range,instead
of going to the first KV of the (row, column) pair and iterating from there. If we don't know
the (row, column), e.g. if it is not specified in the query, we need to go to end of the current
row/column pair first, get a KV from there, and do another seek to (row', column', timerange_max)
from there. We can only skip over to the timerange_max timestamp when we know that there are
no DeleteColumn records at the top of that row/column with a higher timestamp. We can utilize
another Bloom filter keyed on (row, column) to quickly find that out. (From HBASE-4962)

So the motivation is to save seek ops for scanning time-range queries if we know there is
no delete for this row/column. 

>From the implementation perspective, we have already had a delete family bloom filter
which contains all the delete family key values. So we can reuse the same bloom filter for
all other kinds of delete information such as delete columns or delete. 







  was:
To speed up time range scans we need to seek to the maximum timestamp of the requested range,instead
of going to the first KV of the (row, column) pair and iterating from there. If we don't know
the (row, column), e.g. if it is not specified in the query, we need to go to end of the current
row/column pair first, get a KV from there, and do another seek to (row', column', timerange_max)
from there. We can only skip over to the timerange_max timestamp when we know that there are
no DeleteColumn records at the top of that row/column with a higher timestamp. We can utilize
another Bloom filter keyed on (row, column) to quickly find that out. (From HBASE-4962)

So the motivation is to save seek ops for scanning time-range queries if we know there is
no delete for this row/column. 

>From the implementation prospective, we have already had a delete family bloom filter
which contains all the delete family key values. So we can reuse the same bloom filter for
all other kinds of delete information such as delete columns or delete. 







    
> Add other DELETE type information into the delete bloom filter to optimize the time range
query
> -----------------------------------------------------------------------------------------------
>
>                 Key: HBASE-5032
>                 URL: https://issues.apache.org/jira/browse/HBASE-5032
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: Liyin Tang
>            Assignee: Adela Maznikar
>
> To speed up time range scans we need to seek to the maximum timestamp of the requested
range,instead of going to the first KV of the (row, column) pair and iterating from there.
If we don't know the (row, column), e.g. if it is not specified in the query, we need to go
to end of the current row/column pair first, get a KV from there, and do another seek to (row',
column', timerange_max) from there. We can only skip over to the timerange_max timestamp when
we know that there are no DeleteColumn records at the top of that row/column with a higher
timestamp. We can utilize another Bloom filter keyed on (row, column) to quickly find that
out. (From HBASE-4962)
> So the motivation is to save seek ops for scanning time-range queries if we know there
is no delete for this row/column. 
> From the implementation perspective, we have already had a delete family bloom filter
which contains all the delete family key values. So we can reuse the same bloom filter for
all other kinds of delete information such as delete columns or delete. 

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