Cassandra

Cassandraのアーキテクチャ

以下のエントリにまとめた

http://dann.g.hatena.ne.jp/dann/20100313/p2

Cassandra Data Model

• Key (uniquely specifies a “row”)
• Any arbitrary string
• Column families are declared or deleted in advance by administrative action
  • Columns can be added or deleted dynamically
  • Column families have attribute:
    • Name: arbitrary string
    • Type: simple,
• Key can “contain” multiple column families
  • No requirement that two keys have any overlap in columns
  • Columns can be added or removed arbitrarily from column families
• Columns:
  • Name: arbitrary string
  • Value: non-indexed blob
  • Timestamp (client provided)

• Column families have sort orders
  • Time-based sort or name-based sort
• Super-column families:
  • Big tables calls them locality groups
  • Super-column families have a sort order
  • Essentially a multi-column index
• System column families

See also

• http://cwiki.apache.org/confluence/display/CSDR/Data+Model
• http://static.last.fm/johan/nosql-20090611/cassandra_nosql.pdf

TODO

• Range Query
• ConsistencyLevelがQuorumの場合のread処理のまとめ
• Bootstrappingのまとめ