Implementing Native Composite Primary Key Support in Rails 7.1
summary
Rails 7.1 adds native composite primary key support in Active Record with a new query_constraints virtual primary key option, an ID_value attribute to read a lone ID column, and a where by-tuple syntax for bulk loading. Real-world Shopify tests show common selects run 5–6x faster, slow-query volume drops ~80%, while inserts slow ~10x; joint tables and tenant-keyed models benefit most. Associations use composite foreign keys via query_constraints and behave like regular AR associations.
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chapters (16)
- 0:00Introduction to composite keys
- 0:55Speaker introduction
- 1:50Fundamentals and use cases
- 3:04Modeling complex relationships
- 4:38Designing database schemas
- 5:39Multitenant application design
- 6:59Data layout and performance
- 8:08Multitenancy performance tradeoffs
- 9:41Sharding and composite keys
- 11:34Summary of key concepts
- 12:08Active Record 7.1 features
- 15:30Defining composite key models
- 17:08Handling the ID column
- 18:25Associations and constraints
- 20:11Virtual primary keys
- 21:41Conclusion and final notes
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