database-design
Schema design, normalization, indexing, migrations, and query optimization for SQL and NoSQL
Profile →npx skills add cosmicstack-labs/mercury-agent-skills --skill database-design --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# Database Design Design efficient, scalable database schemas. ## Normalization | Normal Form | Rule | Violation Example | |-------------|------|-------------------| | 1NF | Atomic columns, no repeating groups | `phone_numbers: "555-0100,555-0200"` | | 2NF | 1NF + all non-key cols depend on full PK | Orders table with product details | | 3NF | 2NF + no transitive dependencies | Employee with department_name (dept info in dept table) | **When to denormalize**: Read-heavy workloads, reporting, caching layers. ## Indexing Strategy ### Index Types | Index | Use Case | Tradeoff | |-------|----------|----------| | B-Tree | General purpose, equality + range | Default, usually best | | Hash | Equality only | Fast lookups, no sorting | | GIN | Array/JSON | Slightly slower writes | | BRIN | Huge sorted tables | Very small size | ### Rules - Index columns used in WHERE, JOIN, ORDER BY - Index foreign keys - Covering indexes for frequent queries - Don't over-index (slows writes, uses space) - Drop unused indexes (use pg_stat_user_indexes) ## Migrations - One file per change, sequential naming - Always reversible (up/down pair) - Test on staging before production - Run in transactions where pos
- Normalization
- Indexing Strategy
- Index Types
- Rules
- Migrations
- Query Optimization
What does the database-design skill do?
Schema design, normalization, indexing, migrations, and query optimization for SQL and NoSQL
How do I install it?
Run `npx skills add cosmicstack-labs/mercury-agent-skills --skill database-design --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From cosmicstack-labs/mercury-agent-skills, a repository with 364 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.