[jira] [Commented] (HBASE-4435) Add Group By functionality using Coprocessors
[
https://issues.apache.org/jira/browse/HBASE-4435?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanelfocusedCommentId=13255546#comment-13255546
]
lifeng commented on HBASE-4435:
---
when can this patch be put into hbase?
Add Group By functionality using Coprocessors
-
Key: HBASE-4435
URL: https://issues.apache.org/jira/browse/HBASE-4435
Project: HBase
Issue Type: Improvement
Components: coprocessors
Reporter: Nichole Treadway
Priority: Minor
Attachments: HBase-4435.patch
Adds in a Group By -like functionality to HBase, using the Coprocessor
framework.
It provides the ability to group the result set on one or more columns
(groupBy families). It computes statistics (max, min, sum, count, sum of
squares, number missing) for a second column, called the stats column.
To use, I've provided two implementations.
1. In the first, you specify a single group-by column and a stats field:
statsMap = gbc.getStats(tableName, scan, groupByFamily,
groupByQualifier, statsFamily, statsQualifier, statsFieldColumnInterpreter);
The result is a map with the Group By column value (as a String) to a
GroupByStatsValues object. The GroupByStatsValues object has max,min,sum etc.
of the stats column for that group.
2. The second implementation allows you to specify a list of group-by columns
and a stats field. The List of group-by columns is expected to contain lists
of {column family, qualifier} pairs.
statsMap = gbc.getStats(tableName, scan, listOfGroupByColumns,
statsFamily, statsQualifier, statsFieldColumnInterpreter);
The GroupByStatsValues code is adapted from the Solr Stats component.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
[jira] [Commented] (HBASE-4435) Add Group By functionality using Coprocessors
[
https://issues.apache.org/jira/browse/HBASE-4435?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanelfocusedCommentId=13225933#comment-13225933
]
lifeng commented on HBASE-4435:
---
6 millis timeout while waiting for channel to be ready for read. ch :
java.nio.channels.SocketChannel
Add Group By functionality using Coprocessors
-
Key: HBASE-4435
URL: https://issues.apache.org/jira/browse/HBASE-4435
Project: HBase
Issue Type: Improvement
Components: coprocessors
Reporter: Nichole Treadway
Priority: Minor
Attachments: HBase-4435.patch
Adds in a Group By -like functionality to HBase, using the Coprocessor
framework.
It provides the ability to group the result set on one or more columns
(groupBy families). It computes statistics (max, min, sum, count, sum of
squares, number missing) for a second column, called the stats column.
To use, I've provided two implementations.
1. In the first, you specify a single group-by column and a stats field:
statsMap = gbc.getStats(tableName, scan, groupByFamily,
groupByQualifier, statsFamily, statsQualifier, statsFieldColumnInterpreter);
The result is a map with the Group By column value (as a String) to a
GroupByStatsValues object. The GroupByStatsValues object has max,min,sum etc.
of the stats column for that group.
2. The second implementation allows you to specify a list of group-by columns
and a stats field. The List of group-by columns is expected to contain lists
of {column family, qualifier} pairs.
statsMap = gbc.getStats(tableName, scan, listOfGroupByColumns,
statsFamily, statsQualifier, statsFieldColumnInterpreter);
The GroupByStatsValues code is adapted from the Solr Stats component.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
