• Partition Key: Determines which node stores the data (distribution)
• Clustering Key: Determines the sort order within a partition (organization)

CREATE TABLE events (
    user_id UUID,
    event_time TIMESTAMP,
    event_type TEXT,
    data TEXT,
    PRIMARY KEY (user_id, event_time, event_type)
);

• user_id is the partition key
• event_time and event_type are clustering keys
• All events for a user are stored together, sorted by time and type