Data Model Selector

Choose between relational, document, and graph data models for an application by analyzing data shape, relationship complexity, and query patterns. Use when asked "should I use MongoDB or PostgreSQL?", "when does a graph database make sense?", "how do I choose between SQL and NoSQL?", or "what data model fits my access patterns?" Also use for: evaluating impedance mismatch between data model and application code; deciding schema-on-read vs. schema-on-write for heterogeneous data; diagnosing whether many-to-many relationships call for relational or graph model; choosing between property graphs and triple-stores; deciding when polyglot persistence is appropriate. Produces a concrete recommendation with trade-off analysis — not "it depends." Covers relational (PostgreSQL, MySQL), document (MongoDB, CouchDB), and graph (Neo4j, Datomic) models including schema enforcement strategies and data locality trade-offs. For storage engine internals (LSM-tree vs B-tree), use storage-engine-selector instead. For OLTP vs. analytics routing, use oltp-olap-workload-classifier instead.

Install

Claude CodeClawhHubnpxCursorCodexGemini CLI

1. Add marketplace

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

2. Install plugin

› /plugin install designing-data-intensive-applications@bookforge-skills

3. Use the skill

› /data-model-selector

CC-BY-SA · Open sourceGitHub

Source Book

Designing Data-Intensive Applications

Martin Kleppmann

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