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 < masoodmortaz...@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 < > masoodmortaz...@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 + 1nodes >> 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 >> >> > -- Patricio.-
