A super column is a
tuple (a pair) with a binary super column name and a value that maps it to many columns. They consist of a
key–value pairs, where the values are columns. Theoretically speaking, super columns are (
sorted)
associative array of columns.
Similar to a regular
column family {{Short description, A database project that organizes data in packed columns
A column family is a database object that contains columns of related data. It is a tuple (pair) that consists of a key–value pair, where the key is mapped to a value t ...
where a row is a sorted map of column names and column values, a row in a super column family is a sorted map of super column names that maps to column names and column values.
A super column is part of a
keyspace together with other super columns and column families, and columns.
Code example
Written in the
JSON
JSON (JavaScript Object Notation, pronounced ; also ) is an open standard file format and data interchange format that uses human-readable text to store and transmit data objects consisting of attribute–value pairs and arrays (or other ser ...
-like syntax, a super column definition can be like this:
Where:
"databases" are
keyspace;
"Cassandra" and "HBase" are rowKeys;
"name" and "address" are ''super column'' names;
"firstName", "city", "age", etc. are
column
A column or pillar in architecture and structural engineering is a structural element that transmits, through compression, the weight of the structure above to other structural elements below. In other words, a column is a compression member. ...
names.
See also
*
Column (data store)
*
Keyspace (distributed data store)
*
Super column family
References
External links
The Apache Cassandra data model
Data_management
{{database-stub