Cassandra Tables and Schemas

Tables

1. aggregate_events

Stores all events for aggregates.

Schema:

CREATE TABLE aggregate_events (
    aggregateId UUID,
    eventId UUID,
    eventType TEXT,
    data BLOB,
    timestamp TIMESTAMP,
    PRIMARY KEY (aggregateId, timestamp)
) WITH CLUSTERING ORDER BY (timestamp ASC);

2. aggregate_latest_event

Stores the latest event for each aggregate.

Schema:

CREATE TABLE aggregate_latest_event (
    aggregate_id UUID,
    latest_event_id UUID,
    timestamp TIMESTAMP,
    PRIMARY KEY (aggregate_id)
);

3. aggregate_event_count

Stores the count of events for each aggregate.

Schema:

CREATE TABLE aggregate_event_count (
    aggregate_id UUID,
    event_count INT,
    PRIMARY KEY (aggregate_id)
);

4. aggregate_events_version

Stores the version of each event for auditing purposes.

Schema:

CREATE TABLE aggregate_events_version (
    aggregate_id UUID,
    event_id UUID,
    event_version INT,
    timestamp TIMESTAMP,
    PRIMARY KEY (aggregate_id, event_version)
) WITH CLUSTERING ORDER BY (event_version ASC);

5. snapshots

Stores snapshots of aggregates.

Schema:

CREATE TABLE snapshots (
    aggregate_id UUID,
    data BLOB,
    version INT,
    timestamp TIMESTAMP,
    PRIMARY KEY (aggregate_id, timestamp)
) WITH CLUSTERING ORDER BY (timestamp DESC);

Optimization

• Write Operations: Batch operations are used to minimize the number of queries and improve performance.
• Read Operations: Queries are optimized to fetch data using primary keys, ensuring efficient lookups.