| name | database |
| description | Database design, SQL queries, migrations, and optimization. Activate for PostgreSQL, MySQL, SQLite, schema design, queries, indexes, and data modeling. |
| allowed-tools | ["Bash","Read","Write","Edit","Glob","Grep"] |
Database Skill
Provides comprehensive database capabilities for the Golden Armada AI Agent Fleet Platform.
When to Use This Skill
Activate this skill when working with:
- Database schema design
- SQL query writing and optimization
- Database migrations
- Index optimization
- Data modeling
PostgreSQL Quick Reference
Connection
```bash
Connect
psql -h localhost -U postgres -d golden_armada
Connection string
postgresql://user:password@host:5432/database
Common psql commands
\l # List databases
\c database_name # Connect to database
\dt # List tables
\d table_name # Describe table
\di # List indexes
\q # Quit
```
Schema Design
```sql
-- Create table with common patterns
CREATE TABLE agents (
id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
name VARCHAR(100) NOT NULL,
type VARCHAR(50) NOT NULL CHECK (type IN ('claude', 'gpt', 'gemini')),
status VARCHAR(20) DEFAULT 'idle',
config JSONB DEFAULT '{}',
created_at TIMESTAMPTZ DEFAULT NOW(),
updated_at TIMESTAMPTZ DEFAULT NOW(),
deleted_at TIMESTAMPTZ -- Soft delete
);
-- Create index
CREATE INDEX idx_agents_type ON agents(type);
CREATE INDEX idx_agents_status ON agents(status) WHERE deleted_at IS NULL;
CREATE INDEX idx_agents_config ON agents USING GIN(config);
-- Add foreign key
CREATE TABLE tasks (
id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
agent_id UUID NOT NULL REFERENCES agents(id) ON DELETE CASCADE,
message TEXT NOT NULL,
result TEXT,
status VARCHAR(20) DEFAULT 'pending',
created_at TIMESTAMPTZ DEFAULT NOW()
);
```
Common Queries
```sql
-- Basic CRUD
INSERT INTO agents (name, type) VALUES ('agent-1', 'claude') RETURNING *;
SELECT * FROM agents WHERE type = 'claude' AND deleted_at IS NULL;
UPDATE agents SET status = 'active' WHERE id = $1 RETURNING *;
DELETE FROM agents WHERE id = $1;
-- Joins
SELECT a.name, COUNT(t.id) as task_count
FROM agents a
LEFT JOIN tasks t ON a.id = t.agent_id
WHERE a.deleted_at IS NULL
GROUP BY a.id;
-- JSON operations
SELECT * FROM agents WHERE config->>'model' = 'claude-sonnet-4-20250514';
SELECT * FROM agents WHERE config @> '{"enabled": true}';
UPDATE agents SET config = config || '{"version": "2.0"}' WHERE id = $1;
-- Window functions
SELECT
name,
created_at,
ROW_NUMBER() OVER (ORDER BY created_at) as row_num,
LAG(created_at) OVER (ORDER BY created_at) as prev_created
FROM agents;
-- CTEs
WITH active_agents AS (
SELECT * FROM agents WHERE status = 'active'
)
SELECT * FROM active_agents WHERE type = 'claude';
```
Migrations
```sql
-- Migration: 001_create_agents.sql
BEGIN;
CREATE TABLE agents (
id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
name VARCHAR(100) NOT NULL,
type VARCHAR(50) NOT NULL,
created_at TIMESTAMPTZ DEFAULT NOW()
);
CREATE INDEX idx_agents_type ON agents(type);
COMMIT;
-- Rollback: 001_create_agents.sql
BEGIN;
DROP TABLE IF EXISTS agents;
COMMIT;
```
Performance Optimization
```sql
-- Analyze query plan
EXPLAIN ANALYZE SELECT * FROM agents WHERE type = 'claude';
-- Check index usage
SELECT
schemaname,
tablename,
indexname,
idx_scan,
idx_tup_read
FROM pg_stat_user_indexes;
-- Find slow queries
SELECT
query,
calls,
mean_time,
total_time
FROM pg_stat_statements
ORDER BY mean_time DESC
LIMIT 10;
-- Vacuum and analyze
VACUUM ANALYZE agents;
```
SQLAlchemy ORM
```python
from sqlalchemy import Column, String, DateTime, ForeignKey, JSON
from sqlalchemy.dialects.postgresql import UUID
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func
import uuid
class Agent(Base):
tablename = 'agents'
id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
name = Column(String(100), nullable=False)
type = Column(String(50), nullable=False)
status = Column(String(20), default='idle')
config = Column(JSON, default={})
created_at = Column(DateTime(timezone=True), server_default=func.now())
updated_at = Column(DateTime(timezone=True), onupdate=func.now())
tasks = relationship("Task", back_populates="agent", cascade="all, delete-orphan")
class Task(Base):
tablename = 'tasks'
id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
agent_id = Column(UUID(as_uuid=True), ForeignKey('agents.id'), nullable=False)
message = Column(String, nullable=False)
result = Column(String)
agent = relationship("Agent", back_populates="tasks")
```
Best Practices
- Use UUIDs for primary keys in distributed systems
- Add indexes for frequently queried columns
- Use soft deletes (
deleted_at) for important data
- JSONB for flexible data, with GIN indexes
- Foreign key constraints for data integrity
- Created/updated timestamps for auditing
- Connection pooling for performance
