ai-agent/storage/adapters/sqlite_schema.md

SQLite Storage Adapter Schema Documentation

Tables Overview

1. storage (Primary Data Storage)

• key_hash (TEXT, PRIMARY KEY): SHA-256 hash of the storage key
• encrypted_value (BLOB): AES-256 encrypted data value
• created_at (TIMESTAMP): When record was first created
• updated_at (TIMESTAMP): When record was last modified
• created_by (TEXT): User ID who created the record

2. access_log (Audit Trail)

• id (INTEGER, PRIMARY KEY): Auto-incrementing log ID
• key_hash (TEXT): Reference to storage.key_hash
• operation (TEXT): CRUD operation performed
• user_id (TEXT): Who performed the operation
• timestamp (TIMESTAMP): When operation occurred

3. performance_metrics (New in v1.2)

• id (INTEGER, PRIMARY KEY): Auto-incrementing metric ID
• operation (TEXT): CRUD operation type
• execution_time_ms (INTEGER): Operation duration in milliseconds
• timestamp (TIMESTAMP): When operation occurred
• user_id (TEXT): Who performed the operation
• key_hash (TEXT): Optional reference to storage.key_hash

Relationships

erDiagram
    storage ||--o{ access_log : "1:N"
    storage ||--o{ performance_metrics : "1:N"

Example Queries

Get Slow Operations (>500ms)

SELECT operation, execution_time_ms, user_id 
FROM performance_metrics 
WHERE execution_time_ms > 500
ORDER BY execution_time_ms DESC;

Average Operation Times by Type

SELECT 
    operation,
    AVG(execution_time_ms) as avg_time,
    COUNT(*) as operation_count
FROM performance_metrics
GROUP BY operation;

Performance Metrics with Storage Metadata

SELECT 
    pm.operation,
    pm.execution_time_ms,
    s.created_at,
    s.updated_at
FROM performance_metrics pm
LEFT JOIN storage s ON pm.key_hash = s.key_hash;

Version History

• v1.0: Initial schema (storage + access_log)
• v1.1: Added RBAC constraints
• v1.2: Added performance_metrics table