CQL for Cassandra 2.0

Updating a collection

Update the songs table to insert the tags data:

UPDATE songs SET tags = tags + {'2007'}
  WHERE id = 8a172618-b121-4136-bb10-f665cfc469eb;
UPDATE songs SET tags = tags + {'covers'}
  WHERE id = 8a172618-b121-4136-bb10-f665cfc469eb;
UPDATE songs SET tags = tags + {'1973'}
  WHERE id = a3e64f8f-bd44-4f28-b8d9-6938726e34d4;
UPDATE songs SET tags = tags + {'blues'}
  WHERE id = a3e64f8f-bd44-4f28-b8d9-6938726e34d4;
UPDATE songs SET tags = tags + {'rock'}
  WHERE id = 7db1a490-5878-11e2-bcfd-0800200c9a66;

A music reviews list and a schedule (map collection) of live appearances can be added to the table:

ALTER TABLE songs ADD reviews list<text>;
ALTER TABLE songs ADD venue map<timestamp, text>;

Each element of a map, list, or map is internally stored as one Cassandra column. To update a set, use the UPDATE command and the addition (+) operator to add an element or the subtraction (-) operator to remove an element. For example, to update a set:

UPDATE songs
  SET tags = tags + {'rock'}
  WHERE id = 7db1a490-5878-11e2-bcfd-0800200c9a66;

To update a list, a similar syntax using square brackets instead of curly brackets is used.

UPDATE songs
  SET reviews = reviews + [ 'hot dance music' ]
  WHERE id = 7db1a490-5878-11e2-bcfd-0800200c9a66;

To update a map, use INSERT to specify the data in a map collection.

INSERT INTO songs (id, venue)
  VALUES (7db1a490-5878-11e2-bcfd-0800200c9a66,
  { '2013-9-22 12:01'  : 'The Fillmore',
  '2013-10-1 18:00' : 'The Apple Barrel'});

Inserting data into the map replaces the entire map.

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