DbSchema lets you design, manage, and document Apache Cassandra databases. Create ER diagrams, define tables and columns, and generate SQL scripts - with or without a live database connection.
Use Git to share the design, compare it with the Apache Cassandra database, and deploy changes. DbSchema also includes a data editor, query builder, and HTML5 documentation - everything you need in one tool.
Download DbSchema Download Apache Cassandra JDBC Driver
Apache Cassandra is a wide-column distributed database built for linear write scalability and fault tolerance across multiple datacenters. Its schema model is distinct from relational databases: tables are defined by a partition key that determines data distribution, clustering columns that control sort order within a partition, and optional secondary indexes or materialized views for alternative access paths. Designing Cassandra schemas requires thinking in terms of query patterns first, and DbSchema helps teams visualize these structures and document data models clearly.
Cassandra supports a rich set of native data types including collections (list,
set, map), frozen types, and user-defined types (UDTs). DbSchema displays
the full type catalog for each column and renders UDT structures inline in the table definition,
giving architects a complete picture of the data model without running DESCRIBE
commands in cqlsh.
DbSchema's query builder constructs SELECT statements visually against Cassandra tables, respecting partition key constraints that Cassandra enforces at query time. It generates valid CQL and executes queries directly against the cluster, making it practical to explore table contents without memorizing Cassandra's query restrictions.
DbSchema generates HTML documentation from the Cassandra system catalog, including keyspace replication settings, table definitions with partition and clustering key annotations, UDT definitions, and index structures. For distributed system teams, this provides accessible schema documentation without requiring cqlsh access.
DbSchema connects to Cassandra using the DataStax Cassandra JDBC driver. The default native transport
port is 9042. The JDBC URL format is jdbc:cassandra://host:9042/keyspace. For DataStax
Astra DB (cloud-hosted Cassandra), download the secure connect bundle from the Astra console and use
jdbc:cassandra:///keyspace?secureconnectbundle=/path/to/bundle.zip with your Astra
client ID and secret as credentials. If your cluster uses Cassandra's internal authentication
(PasswordAuthenticator), provide a Cassandra username and password in the connection
dialog. SSL is recommended for all production connections.