Super column

The super column consists of a (unique) super column name, and a number of columns.

A super column is a tuple (a pair) with a binary super column name and a value that maps it to many columns.[1] They consist of a key–value pairs, where the values are columns. Theoretically speaking, super columns are (sorted) associative array of columns.[2] Similar to a regular column family 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-like syntax, a super column definition can be like this:

 {
   "mccv": {
     "Tags": {
       "cassandra": {
         "incubator": {"url": "http://incubator.apache.org/cassandra/"},
         "jira": {"url": "http://issues.apache.org/jira/browse/CASSANDRA"}
       },
       "thrift": {
         "jira": {"url": "http://issues.apache.org/jira/browse/THRIFT"}
       }
     }
   }
 }

See also

References

  1. ↑ Sarkissian, Arin (September 1, 2009). "WTF is a SuperColumn". arin.me. Retrieved October 28, 2017. A SuperColumn is a tuple w/ a binary name & a value which is a map containing an unbounded number of Columns - keyed by the Column’s name.
  2. ↑ Ellis, Jonathan (August 15, 2016). "Data Model". Apache Cassandra Wiki. Retrieved October 28, 2017.


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