feat(skills): Add postgres-patterns skill from skill.fish

- Source: affaan-m/everything-claude-code - Covers indexing, data types, common patterns - Anti-pattern detection queries - Added Arbiter-specific context and queries - Updated SKILLS-INDEX.md Chronicler #73
2026-04-09 13:00:23 +00:00
parent 933deb2007
commit 6ff4d3eb64
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--- a/docs/skills/SKILLS-INDEX.md
+++ b/docs/skills/SKILLS-INDEX.md
@@ -169,6 +169,30 @@

 ---

+### postgres-patterns
+**Location:** `docs/skills/postgres-patterns/SKILL.md`  
+**Source:** skill.fish (affaan-m/everything-claude-code)  
+**Triggers:** PostgreSQL, database, SQL, query optimization, indexing, Arbiter database, arbiter_db
+
+**Purpose:** PostgreSQL best practices for schema design, indexing, and query optimization
+
+**What It Covers:**
+- Index type selection (B-tree, GIN, BRIN, composite)
+- Data type best practices
+- Common patterns (UPSERT, cursor pagination, queue processing)
+- Anti-pattern detection queries
+- Configuration templates
+- Arbiter-specific context and useful queries
+
+**Read This When:**
+- Working on Arbiter's database
+- Writing SQL migrations
+- Troubleshooting slow queries
+- Designing new tables
+- Optimizing existing queries
+
+---
+
 ### minecraft-mod-dev
 **Location:** `docs/skills/minecraft-mod-dev/SKILL.md`  
 **Source:** skill.fish (chouzz)  
@@ -303,6 +327,8 @@ docs/skills/
 │   └── SKILL.md
 ├── minecraft-mod-dev/
 │   └── SKILL.md
+├── postgres-patterns/
+│   └── SKILL.md
 └── discord-automation/          (skill collection)
    ├── README.md
    ├── discord-create-channel.md
--- a/docs/skills/postgres-patterns/SKILL.md
+++ b/docs/skills/postgres-patterns/SKILL.md
@@ -0,0 +1,223 @@
+---
+name: postgres-patterns
+description: |
+  PostgreSQL database patterns for query optimization, schema design, indexing, and security.
+  Use this skill when working on Arbiter's database (arbiter_db), writing migrations,
+  troubleshooting slow queries, or implementing security policies.
+source: skill.fish (affaan-m/everything-claude-code)
+---
+
+# PostgreSQL Patterns
+
+Quick reference for PostgreSQL best practices.
+
+---
+
+## WHEN TO ACTIVATE
+
+- Writing SQL queries or migrations
+- Designing database schemas
+- Troubleshooting slow queries
+- Implementing Row Level Security
+- Setting up connection pooling
+- Working on Arbiter's arbiter_db
+
+---
+
+## INDEX CHEAT SHEET
+
+| Query Pattern | Index Type | Example |
+|---------------|------------|---------|
+| `WHERE col = value` | B-tree (default) | `CREATE INDEX idx ON t (col)` |
+| `WHERE col > value` | B-tree | `CREATE INDEX idx ON t (col)` |
+| `WHERE a = x AND b > y` | Composite | `CREATE INDEX idx ON t (a, b)` |
+| `WHERE jsonb @> '{}'` | GIN | `CREATE INDEX idx ON t USING gin (col)` |
+| `WHERE tsv @@ query` | GIN | `CREATE INDEX idx ON t USING gin (col)` |
+| Time-series ranges | BRIN | `CREATE INDEX idx ON t USING brin (col)` |
+
+---
+
+## DATA TYPE QUICK REFERENCE
+
+| Use Case | Correct Type | Avoid |
+|----------|--------------|-------|
+| IDs | `bigint` | `int`, random UUID |
+| Strings | `text` | `varchar(255)` |
+| Timestamps | `timestamptz` | `timestamp` |
+| Money | `numeric(10,2)` | `float` |
+| Flags | `boolean` | `varchar`, `int` |
+
+---
+
+## COMMON PATTERNS
+
+### Composite Index Order
+
+```sql
+-- Equality columns first, then range columns
+CREATE INDEX idx ON orders (status, created_at);
+-- Works for: WHERE status = 'pending' AND created_at > '2024-01-01'
+```
+
+### Covering Index
+
+```sql
+CREATE INDEX idx ON users (email) INCLUDE (name, created_at);
+-- Avoids table lookup for SELECT email, name, created_at
+```
+
+### Partial Index
+
+```sql
+CREATE INDEX idx ON users (email) WHERE deleted_at IS NULL;
+-- Smaller index, only includes active users
+```
+
+### RLS Policy (Optimized)
+
+```sql
+CREATE POLICY policy ON orders
+  USING ((SELECT auth.uid()) = user_id);  -- Wrap in SELECT!
+```
+
+### UPSERT
+
+```sql
+INSERT INTO settings (user_id, key, value)
+VALUES (123, 'theme', 'dark')
+ON CONFLICT (user_id, key)
+DO UPDATE SET value = EXCLUDED.value;
+```
+
+### Cursor Pagination
+
+```sql
+SELECT * FROM products WHERE id > $last_id ORDER BY id LIMIT 20;
+-- O(1) vs OFFSET which is O(n)
+```
+
+### Queue Processing
+
+```sql
+UPDATE jobs SET status = 'processing'
+WHERE id = (
+  SELECT id FROM jobs WHERE status = 'pending'
+  ORDER BY created_at LIMIT 1
+  FOR UPDATE SKIP LOCKED
+) RETURNING *;
+```
+
+---
+
+## ANTI-PATTERN DETECTION
+
+### Find Unindexed Foreign Keys
+
+```sql
+SELECT conrelid::regclass, a.attname
+FROM pg_constraint c
+JOIN pg_attribute a ON a.attrelid = c.conrelid AND a.attnum = ANY(c.conkey)
+WHERE c.contype = 'f'
+  AND NOT EXISTS (
+    SELECT 1 FROM pg_index i
+    WHERE i.indrelid = c.conrelid AND a.attnum = ANY(i.indkey)
+  );
+```
+
+### Find Slow Queries
+
+```sql
+SELECT query, mean_exec_time, calls
+FROM pg_stat_statements
+WHERE mean_exec_time > 100
+ORDER BY mean_exec_time DESC;
+```
+
+### Check Table Bloat
+
+```sql
+SELECT relname, n_dead_tup, last_vacuum
+FROM pg_stat_user_tables
+WHERE n_dead_tup > 1000
+ORDER BY n_dead_tup DESC;
+```
+
+---
+
+## CONFIGURATION TEMPLATE
+
+```sql
+-- Connection limits (adjust for RAM)
+ALTER SYSTEM SET max_connections = 100;
+ALTER SYSTEM SET work_mem = '8MB';
+
+-- Timeouts
+ALTER SYSTEM SET idle_in_transaction_session_timeout = '30s';
+ALTER SYSTEM SET statement_timeout = '30s';
+
+-- Monitoring
+CREATE EXTENSION IF NOT EXISTS pg_stat_statements;
+
+-- Security defaults
+REVOKE ALL ON SCHEMA public FROM public;
+
+SELECT pg_reload_conf();
+```
+
+---
+
+## FIREFROST CONTEXT
+
+### Arbiter Database (arbiter_db)
+
+**Location:** Command Center (63.143.34.217)
+**User:** arbiter
+**Password:** (see .env on Command Center)
+
+**Current Tables:**
+- `subscriptions` — Stripe subscription tracking
+- `users` — Discord user data
+- `servers` — Pterodactyl server allocations
+- `whitelist_entries` — Server whitelist management
+
+**When optimizing Arbiter:**
+- Check for missing indexes on foreign keys
+- Use `timestamptz` for all time columns
+- Consider partial indexes for active subscriptions
+- Use cursor pagination for listing endpoints
+
+---
+
+## USEFUL QUERIES FOR ARBITER
+
+### Check Index Usage
+
+```sql
+SELECT relname, indexrelname, idx_scan, idx_tup_read
+FROM pg_stat_user_indexes
+ORDER BY idx_scan DESC;
+```
+
+### Check Table Sizes
+
+```sql
+SELECT relname, pg_size_pretty(pg_total_relation_size(relid))
+FROM pg_stat_user_tables
+ORDER BY pg_total_relation_size(relid) DESC;
+```
+
+### Active Connections
+
+```sql
+SELECT count(*), state
+FROM pg_stat_activity
+WHERE datname = 'arbiter_db'
+GROUP BY state;
+```
+
+---
+
+**Source:** skill.fish — affaan-m/everything-claude-code (Based on Supabase Agent Skills, MIT License)
+**Added:** 2026-04-09 by Chronicler #73
+
+**Fire + Frost + Foundation = Where Love Builds Legacy** 💙🔥❄️