Hi all, is there any documentation for:

 ConsistencyLevel.DCQUORUM  and  ConsistencyLevel.DCQUORUMSYNC ?

DC = Data Center ?

Thanks

On Thu, Feb 25, 2010 at 12:12 PM, Masood Mortazavi <masoodmortazavi@gmail.com> wrote:
From the code, it appears that for "get" the default is ONE.
  Column column = thriftClient_.get(tableName, key, path, ConsistencyLevel.ONE).column
- m.


On Thu, Feb 25, 2010 at 11:08 AM, Masood Mortazavi <masoodmortazavi@gmail.com> wrote:


What is the write and read consistency level for the CLI tool "cassandra-cli" ?

Do the "set" and "get" commands in the "cli" allow the Consistency Level to be specified for a given "set" or "get"?

Is there a current specification of CLI anywhere on the wiki?

( How are JIRA's related to the CLI tagged in the JIRA system assuming they are "tagged" separately? In other words, is there an identifier for them? )

Regards,
m.

==========================
The Cassandra "API" describes write and read consistency levels as follows:
http://wiki.apache.org/cassandra/API

Write

Level

Behavior

ZERO

Ensure nothing. A write happens asynchronously in background

ANY

(Coming in 0.6) Ensure that the write has been written to at least 1 node, including hinted recipients.

ONE

Ensure that the write has been written to at least 1 node's commit log and memory table before responding to the client.

QUORUM

Ensure that the write has been written to <ReplicationFactor> / 2 + 1 nodes before responding to the client.

ALL

Ensure that the write is written to all <ReplicationFactor> nodes before responding to the client. Any unresponsive nodes will fail the operation.

Read

Level

Behavior

ZERO

Not supported, because it doesn't make sense.

ANY

Not supported. You probably want ONE instead.

ONE

Will return the record returned by the first node to respond. A consistency check is always done in a background thread to fix any consistency issues when ConsistencyLevel.ONE is used. This means subsequent calls will have correct data even if the initial read gets an older value. (This is called read repair.)

QUORUM

Will query all storage nodes and return the record with the most recent timestamp once it has at least a majority of replicas reported. Again, the remaining replicas will be checked in the background.

ALL

Will query all storage nodes and return the record with the most recent timestamp once all nodes have replied. Any unresponsive nodes will fail the operatio






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Patricio.-