org.apache.hadoop.hbase.client.Consistency Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
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* distributed under the License is distributed on an "AS IS" BASIS,
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package org.apache.hadoop.hbase.client;
import org.apache.yetus.audience.InterfaceAudience;
/**
* Consistency defines the expected consistency level for an operation.
*/
@InterfaceAudience.Public
public enum Consistency {
// developer note: Do not reorder. Client.proto#Consistency depends on this order
/**
* Strong consistency is the default consistency model in HBase,
* where reads and writes go through a single server which serializes
* the updates, and returns all data that was written and ack'd.
*/
STRONG,
/**
* Timeline consistent reads might return values that may not see
* the most recent updates. Write transactions are always performed
* in strong consistency model in HBase which guarantees that transactions
* are ordered, and replayed in the same order by all copies of the data.
* In timeline consistency, the get and scan requests can be answered from data
* that may be stale.
*
* The client may still observe transactions out of order if the requests are
* responded from different servers.
*/
TIMELINE,
}