Inheritance Mapping Selector

Select the correct ORM inheritance strategy — Single Table Inheritance (STI), Class Table Inheritance (joined table / Multi-Table Inheritance), or Concrete Table Inheritance (table per class) — for any OO inheritance hierarchy that needs to be persisted in a relational database. Use when asked: "which inheritance mapping should I use?", "single table vs joined table inheritance", "STI vs CTI vs table per class", "Hibernate inheritance strategy SINGLE_TABLE vs JOINED vs TABLE_PER_CLASS", "@Inheritance JPA", "Rails STI vs multi-table inheritance", "Django model inheritance type", "how to map inheritance in database", "inheritance in database design", "discriminator column inheritance", "ORM polymorphic query performance", "polymorphic table design", "table per class inheritance trade-offs", "joined inheritance vs single table", "inheritance schema design". Applies at greenfield schema design, ORM configuration, or legacy schema refactoring. Routes to the right strategy on six trade-off dimensions: joins on polymorphic read, wasted column space, FK-constraint enforceability, ad-hoc query readability, refactoring impact, and polymorphism-query cost. Identifies when mixing strategies via Inheritance Mappers is warranted (hierarchy branches with divergent trade-offs). Maps each strategy to idiomatic ORM config: Hibernate/JPA `@Inheritance(SINGLE_TABLE/JOINED/TABLE_PER_CLASS)`, Rails STI type column, Django Multi-Table Inheritance vs abstract base. Produces an inheritance mapping decision record with schema sketch and ORM config snippet.

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Install

Claude CodeClawhHubnpxCursorCodexGemini CLI

1. Add marketplace

› /plugin marketplace add bookforge-ai/bookforge-skills

2. Install plugin

› /plugin install patterns-of-enterprise-application-architecture@bookforge-skills

3. Use the skill

› /inheritance-mapping-selector

CC-BY-SA · Open sourceGitHub

Source Book

Patterns of Enterprise Application Architecture

Martin Fowler, David Rice, Matthew Foemmel, Edward Hieatt, Robert Mee, Randy Stafford

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