[FEATURE] Schema Drift Detection

[iamvirul]

Feature Description

Comprehensive schema drift detection that identifies structural differences between production and development databases, including table-level and column-level differences.

Status

Implemented in: v0.1
Status: Completed

Implementation Details

Detection Capabilities

• Table-level differences (missing tables, extra tables)
• Column-level differences (missing columns, extra columns)
• Column type mismatches
• Nullable constraint differences
• Primary key detection and validation

Reporting

• JSON format schema diff reports
• Human-readable text format reports
• Detailed column-by-column comparison
• Table-by-table breakdown

Commands

• deepdiffdb schema-diff - Standalone schema comparison
• Integrated into deepdiffdb diff and deepdiffdb gen-pack

Database Support

• MySQL (via INFORMATION_SCHEMA)
• PostgreSQL (via INFORMATION_SCHEMA)
• SQLite (via sqlite_master)

Technical Implementation

• Schema introspection using database metadata
• Normalized schema model
• Driver-specific query optimization
• PostgreSQL schema-aware queries

Features

• Detects missing tables in either database
• Identifies column differences
• Reports type mismatches
• Validates primary key requirements
• Respects ignore lists

Use Cases

1. Pre-Migration Validation:

   • Check for schema drift before data migration
   • Identify structural differences
   • Prevent migration failures

2. Schema Synchronization:

   • Track schema changes over time
   • Identify drift between environments
   • Document schema differences

3. Development Workflow:

   • Validate schema consistency
   • Catch schema drift early
   • Ensure production readiness

Impact

• Prevents data migration failures
• Enables schema validation
• Foundation for schema migration generation

Related Features

• Schema migration generation (partial in v0.2, enhanced in v0.3)
• Primary key validation
• Ignore list support

[coderabbitai]

📝 CodeRabbit Plan Mode

Generate an implementation plan and prompts that you can use with your favorite coding agent.

• Create Plan

Examples

• Example 1
• Example 2

---

🔗 Similar Issues

Related Issues

• [FEATURE] Core Database Diff Engine #19
• [FEATURE] Schema Migration Generator #8
• [FEATURE] HTML Report Viewer #10

🔗 Related PRs

#1 - test: Add comprehensive test coverage with testcontainers integration tests [merged]

👤 Suggested Assignees

• iamvirul

---

🧪 Issue enrichment is currently in open beta.

You can configure auto-planning by selecting labels in the issue_enrichment configuration.

To disable automatic issue enrichment, add the following to your .coderabbit.yaml:

issue_enrichment:
  auto_enrich:
    enabled: false

💬 Have feedback or questions? Drop into our discord or schedule a call!