Databases skills for Codex
Skills for data that has to stay correct and fast: PostgreSQL indexing, query tuning, RLS and partitioning, zero-downtime migrations, MySQL and SQLite in production, ORMs such as Prisma, Drizzle, SQLAlchemy and Active Record, plus MongoDB, Redis, DynamoDB, ClickHouse, Supabase and Firestore.
curl -fsSL codexskills.dev/install.sh | sh -s -- --category databases Installs all 38 into ~/.agents/skills/. Or download the zip.
All 38 Databases skills
Each opens the full SKILL.md, example prompts and every way to install it.
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Active Record Performance
Faster Rails queries, proven with numbers -
Cassandra Data Modeling
One partition per query, no surprises at scale -
ClickHouse Analytics
Sorting keys and rollups that read fewer granules -
Connection Pooling
Fit every pool inside max_connections -
Data Backfills
Touch 80 million rows without anyone noticing -
Database Observability
Know which query, table or slot is hurting you -
Database Seeding
Rerunnable seeds that look like production -
Database Transactions
Stop lost updates, write skew and deadlocks -
Django ORM Performance
Measure the queryset, then fix the actual cause -
Drizzle ORM
TypeScript schema in, reviewed SQL migrations out -
DynamoDB Single-Table Design
Every access pattern is one Query, checked by script -
Elasticsearch Mappings
Change mappings without taking search down -
Firebase Firestore
Predictable reads, tested rules, versioned indexes -
Kysely Query Builder
SQL you would write by hand, checked by tsc -
libSQL and Turso
Local-speed reads with a remote SQLite primary -
MongoDB Aggregation
Pipelines that hit indexes and stay under limits -
MongoDB Schema Design
Model documents from the queries they serve -
MySQL Online Schema Change
ALTER huge MySQL tables while traffic flows -
MySQL Tuning
InnoDB-aware indexes, plans and settings -
N+1 Query Fixes
Constant query counts, whatever the page size -
Neo4j Graph Modeling
Graph models built from the questions you ask -
Postgres Backup and Restore
Backups proven by a timed restore drill -
Postgres Indexing
Index from query plans, not hunches -
Postgres JSONB
Flexible JSON without slow, unindexed queries -
Postgres Partitioning
Retention by DROP TABLE, not by DELETE -
Postgres Query Tuning
Read the plan, fix the estimate, then measure -
Postgres Row-Level Security
Tenant isolation that holds when a WHERE is forgotten -
Postgres Schema Design
Make invalid rows impossible to insert -
Prisma ORM
Reviewed migrations, lean queries, Prisma 7 ready -
Redis Data Structures
The right Redis type, key and expiry per job -
Serverless Postgres
Pooled at runtime, direct for migrations, branched per PR -
SQL Query Review
Catch fan-out, NULL and injection bugs before merge -
SQL Window Functions
Rankings and running totals that are actually right -
SQLAlchemy 2.0
Typed models, scoped sessions, lazy loads that raise -
SQLite in Production
WAL, short writes and backups that restore -
Supabase Backend
Migrations, RLS and auth checks that hold up -
TimescaleDB
Hypertables that stay fast after a billion rows -
Zero-Downtime Migrations
Change big tables without a lock-queue outage
No Databases skill matches that.
Where to start
Install the ones that match requests you make every week. Name one with $data-backfills when you want it for sure; otherwise Codex picks by description.
Start with
- Data BackfillsTouch 80 million rows without anyone noticing
- Prisma ORMReviewed migrations, lean queries, Prisma 7 ready
- Zero-Downtime MigrationsChange big tables without a lock-queue outage
Install a few by name
curl -fsSL codexskills.dev/install.sh | sh -s -- active-record-performance cassandra-data-modeling 104-line POSIX script. No sudo, no telemetry. Read install.sh
Databases FAQ
How do I install every Databases skill at once?
Run curl -fsSL https://codexskills.dev/install.sh | sh -s -- --category databases to put all 38 in ~/.agents/skills/, or add --project to install them into the current repository's .agents/skills/. You can also download the category zip and unpack it yourself.
Does installing 38 skills slow Codex down?
Hardly. At startup Codex sees only each skill's name and description, a few dozen words apiece, and reads a full SKILL.md only when a task needs it. Install the whole category if the work fits; unused skills cost almost nothing.
Which Databases skill should I start with?
Start with Data Backfills, Prisma ORM, Zero-Downtime Migrations. They cover the requests that come up most in this category. Mention one with $data-backfills to try it.