[
https://issues.apache.org/jira/browse/HBASE-19826?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16355259#comment-16355259
]
Ankit Singhal commented on HBASE-19826:
---------------------------------------
bq. So what if a compaction happens before you run the tool? The cell will be
deleted in compaction if you do not have KeepDeleteCells.TRUE, then either you
use time range scan or not you can never read it anymore...
By default, we actually cap the scan in IndexScrutinyTool to the current
timestamp just in order to avoid in-flight writes/Deletes and don't expect
these in-flight writes to get compacted during the same time. But depending on
the write rate, this surely can happen. [~jamestaylor] , do you have any idea
if we handle this case as well somewhere?
> Provide a option to see rows behind a delete in a time range queries
> --------------------------------------------------------------------
>
> Key: HBASE-19826
> URL: https://issues.apache.org/jira/browse/HBASE-19826
> Project: HBase
> Issue Type: Improvement
> Reporter: Ankit Singhal
> Assignee: Ankit Singhal
> Priority: Major
> Fix For: 2.0.0
>
>
> We can provide an option (something like seePastDeleteMarkers) in a scan to
> let the user see the versions behind the delete marker even if
> keepDeletedCells is set to false in the descriptor.
> With the previous version, we workaround the same in preStoreScannerOpen
> hook. For reference PHOENIX-4277
> {code}
> @Override
> public KeyValueScanner preStoreScannerOpen(final
> ObserverContext<RegionCoprocessorEnvironment> c,
> final Store store, final Scan scan, final NavigableSet<byte[]>
> targetCols,
> final KeyValueScanner s) throws IOException {
>
> if (scan.isRaw() ||
> ScanInfoUtil.isKeepDeletedCells(store.getScanInfo()) ||
> scan.getTimeRange().getMax() == HConstants.LATEST_TIMESTAMP ||
> TransactionUtil.isTransactionalTimestamp(scan.getTimeRange().getMax())) {
> return s;
> }
>
> ScanInfo scanInfo =
> ScanInfoUtil.cloneScanInfoWithKeepDeletedCells(store.getScanInfo());
> return new StoreScanner(store, scanInfo, scan, targetCols,
>
> c.getEnvironment().getRegion().getReadpoint(scan.getIsolationLevel()));
> }
> {code}
> Another way is to provide a way to set KEEP_DELETED_CELLS to true in
> ScanOptions of preStoreScannerOpen.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
