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https://issues.apache.org/jira/browse/HBASE-13890?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14615894#comment-14615894
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Vladimir Rodionov commented on HBASE-13890:
-------------------------------------------
The new API was added to *OperationsWithAttributes*:
{code}
/**
* This method allows you to set in-memory-only operation mode.
* Queries: Get and Scan as well as Increment and Append will
* work only on data in RAM (MemStore).
* If data is missing in RAM, the following will be returned:
* Empty Result for Get, Increment, Append and Scan
*
*/
public OperationWithAttributes setMemstoreOnly(boolean v){
setAttribute(MEMSTORE_ONLY_ATTRIBUTE, Bytes.toBytes(v));
return this;
}
/**
* Checks if we are in-memory-only mode
* @return true, if yes
*/
public boolean isMemstoreOnly(){
byte[] attr = getAttribute(MEMSTORE_ONLY_ATTRIBUTE);
return attr != null && Bytes.toBoolean(attr) == true;
}
{code}
> Get/Scan from MemStore only (Client API)
> ----------------------------------------
>
> Key: HBASE-13890
> URL: https://issues.apache.org/jira/browse/HBASE-13890
> Project: HBase
> Issue Type: New Feature
> Components: API, Client, Scanners
> Reporter: Vladimir Rodionov
> Assignee: Vladimir Rodionov
> Attachments: HBASE-13890-v1.patch
>
>
> This is short-circuit read for get/scan when recent data (version) of a cell
> can be found only in MemStore (with very high probability).
> Good examples are: Atomic counters and appends. This feature will allow to
> bypass completely store file scanners and improve performance and latency.
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