Database Reference
In-Depth Information
there remain many skeptics (“nonbelievers”) of such a model. It is further speculated that by
naming the database Cassandra, after the Greek seer of the future, its creators are making a
kind of joking reference to the Oracle database.
The Java client
Hector
by Ran Tavory is named for Cassandra's brother.
Chiitton
In ancient Greece, a chiton was a cloth garment, typically sleeveless, worn by both men
and women. It is the namesake for the open source project Chiton by Brandon Williams,
which is a Python GTK-based browser for Apache Cassandra. It is currently hosted at
ht-
A related project is Telephus, a low-level client API for Cassandra written in Twisted Python.
It is currently hosted at
http://github.com/driftx/Telephus
.
Cllustter
A cluster is two or more Cassandra instances acting in concert. These instances communicate
When you configure a new instance to introduce to your cluster, you'll need to do a few
things. First, indicate a
Seed Node
. Next, indicate the ports on which Cassandra should listen
Tool
to verify that it is set up correctly.
Collumn
A column is the most basic unit of representation in the Cassandra data model. A column is
a triplet of a name (sometimes referred to as a “key”), a value, and a timestamp. A column's
values, including the timestamp, are all supplied by the client. The data type for the name
and value are Java byte arrays. The data type for the timestamp is a long primitive. Columns
are immutable in order to prevent multithreading issues.
Columns are organized into column families.
The column is defined in Cassandra by the
org.apache.cassandra.db.IColumn
interface,
which allows a variety of operations, including getting the value of the column as a
byte[]
or getting its subcolumns as a
Collection<IColumn>
, and finding the time of the most re-
cent change.
Columns are sorted by their type, which is one of
AsciiType
,
BytesType
,
Lexic-
alUUIDType
,
LongType
,
TimeUUIDType
,
UTF8Type
.
See also
Column Family
.
