Database Designer

The agent analyzes SQL schemas for normalization compliance, recommends optimal indexes based on query patterns, and generates safe migration scripts with rollback procedures. It produces Mermaid ERDs, detects redundant indexes, and implements zero-downtime expand-contract migration patterns for PostgreSQL and MySQL.

Core Capabilities

• Schema analysis — detect normalization violations (1NF-BCNF), missing constraints, naming issues, and data-type problems from DDL or JSON.
• ERD generation — produce valid Mermaid entity-relationship diagrams from declared relationships.
• Index optimization — recommend indexes from query patterns, order composite columns by selectivity, detect redundant/overlapping indexes, and find covering-index opportunities.
• Migration generation — forward + rollback SQL between schema versions, with validation queries.
• Zero-downtime migrations — expand-contract pattern with safe backfill for tables with 10M+ rows.
• Database selection guidance — match workload requirements to PostgreSQL, MySQL, MongoDB, or DynamoDB.

When to Use

• Designing or reviewing a new schema for normalization and constraints.
• Optimizing queries by recommending or pruning indexes.
• Planning a safe (optionally zero-downtime) migration between schema versions.
• Analyzing database performance and relationship structure (ERD).
• Choosing the right database technology for a workload.