Databases Reference
In-Depth Information
Column Family
Column family stores are modeled on
Google's BigTable
.
The data model is based on a
sparsely populated table whose rows can contain arbitrary columns, the keys for which
provide natural indexing.
In our discussion we'll use terminology from Apache Cassandra. Cas‐
sandra isn't necessarily a faithful interpretation of BigTable, but it is
widely deployed, and its terminology is well understood.
In
Figure A-4
we see the four common building blocks used in column family databases.
The simplest unit of storage is the
column
itself, consisting of a name-value pair. Any
number of columns can be combined into a
super column
, which gives a name to a
sorted set of columns. Columns are stored in rows, and when a row contains columns
only, it is known as a
column family
. When a row contains super columns, it is known
as a
super column family
.
Figure A-4. The four building blocks of column family storage
