Cassandra

The Cassandra data source supports Cassandra server versions 1.2.x and upwards, and works with Cassandra Query Language version 3 (CQL3).

You can create your Cassandra data source as you create the data service: Follow the steps from 1 to 3 in creating a data service using various data sources. When you get to the Add New Data Source screen, select Cassandra as the data source type. The Cassandra-specific options will be available for editing.

The following describes the properties supported by the Cassandra datasource. For more detailed information about the functionality of the underlying connector, check http://www.datastax.com/documentation/developer/java-driver/2.0/index.html.

Data Source Property	Description
Cassandra Servers*	Comma separated list of host names of Cassandra servers.
Port	The port of Cassandra servers.
Cluster Name	The Cassandra cluster name.
Compression	Compression used in communication.
User Name	The authenticating user's username.
Password	The authenticating user's password.
Load Balancing Policy	The client load balancing policy on how calls should be made to the provided servers.
Enable JMX Reporting	Enable JMX statistics of the connector.
Enable Metrics	Enable metrics of the connector.
Local Core Connections Per Host	Connection pooling: Local core connections per server host.
Remote Core Connections Per Host	Connection pooling: Remote core connections per server host.
Local Max.Connections Per Host	Connection pooling: Maximum local connections per server host.
Remote Max.Connections Per Host	Connection pooling: Remote max connections per server host.
Local Max.Simultaneous Requests Per Connection Threshold	Connection pooling: Number of simultaneous requests on all local connections to a host. If the number of requests exceeds this number, new connections are created.
Remote Max.Simultaneous Requests Per Connection Threshold	Connection pooling: Number of simultaneous requests on all remote connections to a host. If the number of requests exceeds this number, new connections are created.
Local Min.Simultaneous Requests Per Connection Threshold	Connection pooling: Number of simultaneous requests on a connection. If the number of requests is less than this number, the remote connections in excess are reclaimed.
Remote Min.Simultaneous Requests Per Connection Threshold	Connection pooling: Number of simultaneous requests on a connection. If the number of requests is less than this number, the remote connections in excess are reclaimed.
Protocol Version	The native protocol version to use. By default, it auto connects. "2" for Cassandra versions 2.0 and upwards, and "1" for Cassandra version 1.2.x.
Consistency Level	The consistency level used for queries.
Fetch Size	Fetch size used by queries.
Serial Consistency Level	The serial consistency level used for queries.
Reconnection Policy	The reconnection policy used for the cluster.
Constant Reconnection Policy Delay	If "ConstantReconnectionPolicy" is used for Reconnection Policy, this represents the constant wait time between reconnection attempts in milliseconds.
Exponential Reconnection Policy Base Delay	If "ExponentialReconnectionPolicy" is used for Reconnection Policy, this represent the base delay in milliseconds.
Exponential Reconnection Policy Max. Delay	If "ExponentialReconnectionPolicy" is used for Reconnection Policy, this represent the maximum delay in milliseconds.
Retry Policy	Configured the retry policy in this cluster.
Connection Timeout	The socket connection timeout in milliseconds.
The socket connection timeout in milliseconds.	Set if socket keeps alive.
Keep Alive	Set if socket keeps alive.
Read Timeout	Set per host socket read timeout in milliseconds.
Receive Buffer Size	The socket receive buffer size.
Send Buffer Size	The socket send buffer size.
Reuse Address	The socket re-use address.
So Linger	The socket linger on value.
TCP no Delay	Set socket TCP to no delay.
Disable Native Batch Requests	Disables native Cassandra batch requests, and reverts to emulated batch requests.

* Mandatory fields.

To write a query to this datasource, see Writing Data Service Queries.

Queries based on Cassandra datasources, currently do not support named parameters or array type parameters.

A sample based on the Cassandra datasource can be found here: Cassandra Sample.