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stack commented on HADOOP-2291: ------------------------------- What is state of this issue Edward? Will it not work on billions of rows? Other comments on the patch are: + We should add a HTable.getTableDescriptor and a HTable.getColumnFamilies? + Comments would be helpful. For example would be good to explain why you of a sudden set a variable 'i' equal to 2 and a comment confirming what you are doing finding midkeys over and over again would be helpful (Won't this take a long time on a big table)? + If in your search for endKey turns up a null, won't you get a NPE when you convert back from base64? + Would suggest that the estimator or an estimator override take as inputs the smallest slice to start with and the largest slice that the estimator should try. > [hbase] Add row count estimator > ------------------------------- > > Key: HADOOP-2291 > URL: https://issues.apache.org/jira/browse/HADOOP-2291 > Project: Hadoop > Issue Type: New Feature > Components: contrib/hbase > Reporter: stack > Assignee: Edward Yoon > Priority: Minor > Attachments: 2291_v01.patch, Keying.java > > > Internally we have a little tool that will do a rough estimate of how many > rows there are in a dataHbase. It keeps getting larger and larger partitions > running scanners until it turns up > N occupied rows. Once it has a number > > N, it multiples by the partition size to get an approximate row count. > This issue is about generalizing this feature so it could sit in the general > hbase install. It would look something like: > {code} > long getApproximateRowCount(final Text startRow, final Text endRow, final > long minimumCountPerPartition, final long maximumPartitionSize) > {code} > Larger minimumCountPerPartition and maximumPartitionSize values would make > the count more accurate but would mean the method ran longer. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.