Table of Contents
1 General
1.1 Row-oriented
- Paritioned row store, in which data is stored in sparse multidimensional hashtables.
- sparse = any given row can have one or more columns, but each row doesn't have to have all the same columns
- paritioned = each row has unique key which makes data accessible
- Keys distribute the rows across multiple data stores.
- Cassandra stores data in a multidimensional, sorted hash table.
- Data stored in each column is stored as a seperate entry in the hash table.
2 Data model
- Column
- is a name/value pair
- Row
- is a container for columns referenced by a primary key/row key
- Table
- is a container of rows
- Keyspace
- is a container for tables
- Cluster
- is a container for keyspaces that spans one or more nodes
2.1 Clusters
Cassandra is designed to be distributed over several machines operating together that appear as a single instance → cluster, also called ring, is the outermost structure.
2.2 Keyspaces
- Outermost container for data
- Container for tables
- Defined by a name and set of attributes
2.3 Tables
- Container of an ordered collection of rows
- Where each row is a container of columns
- Ordering is determined by the columns, which are identified as keys
3 Testing
You use the cassandra-stress tool together with some user-defined YAML files.
Is quite flexible and functions really well for quickly testing schemas.