ScyllaDB Data Modeling

CQL data modeling patterns and anti-patterns for ScyllaDB. Bad schema is the root cause of most ScyllaDB performance issues — no amount of cluster scaling can fix a fundamentally wrong data model.

When to Apply

Reference these guidelines when:

• Designing a new ScyllaDB schema from scratch
• Migrating from SQL/relational databases, MongoDB, or Cassandra to ScyllaDB
• Reviewing existing table designs for performance issues
• Troubleshooting slow queries, timeouts, or hot nodes
• Deciding how to structure primary keys (partition key + clustering columns)
• Modeling time-series, IoT, or event data
• Seeing large partition warnings in logs
• Encountering ALLOW FILTERING in queries or code reviews
• Adding secondary indexes or materialized views

Key Principle