Cassandra is a structured store. It has a rich data model that goes beyond a simple key-value model. This is a good thing as some of the complexity can be pushed to Cassandra, leading to simpler and more efficient applications. This post walks through the different data model elements.
Data model elements
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A sorted associative array of columns.
A container for columns sorted by their names. Column Families are referenced and sorted by row keys.
Super Column Family
A container for super columns sorted by their names. Like Column Families, Super Column Families are referenced and sorted by row keys.
Top level element of a schema. Container for column families.
These examples are extracted from the model of a simple twitter clone discussed here. I picked the statuses column family and the user relationships super column family.