# GORM → sqlc + pgx Decision Summary

## The Question
"Are you sure GORM is the best over sqlc+pgx given the complexity of code?"

## The Answer
**YES, you were absolutely right.** sqlc + pgx is the better choice for TraceRTM.

## Why sqlc + pgx Wins

### 1. **Complex Query Patterns** ✅
TraceRTM requires:
- Recursive CTEs for graph traversal (descendants, impact analysis)
- Transitive closure queries
- Complex joins across 16 views
- Temporal queries with time-travel
- **GORM struggles with these** - you end up writing raw SQL anyway

### 2. **Type Safety Without Reflection** ✅
- sqlc generates type-safe Go code from SQL at compile time
- No runtime reflection overhead (GORM's weakness)
- Compile-time verification of queries
- Better performance for complex queries

### 3. **Performance** ✅
- Direct pgx driver (no ORM overhead)
- Prepared statements with proper caching
- Better for 1000+ concurrent agents
- Lower memory footprint
- Faster query execution

### 4. **Explicit SQL** ✅
- All queries are explicit and auditable
- Easier to optimize with EXPLAIN ANALYZE
- Better for compliance/traceability requirements
- Easier to understand data flow
- Perfect for a requirements traceability system!

### 5. **Graph Queries** ✅
- Recursive CTEs are first-class citizens
- Can express complex relationship traversals
- Better for the 60+ link types
- Supports all graph patterns needed

## What Changed

### Files Updated
1. **backend/go.mod** - Replaced GORM with pgx
2. **backend/main.go** - Updated to use pgxpool
3. **backend/internal/database/database.go** - Rewrote for pgx
4. **backend/README.md** - Updated documentation

### Files Created
1. **backend/schema.sql** - Database schema (CREATE TABLE statements)
2. **backend/queries.sql** - SQL queries for sqlc to generate
3. **backend/sqlc.yaml** - sqlc configuration
4. **backend/SQLC_MIGRATION_GUIDE.md** - Comprehensive migration guide

## Next Steps

### 1. Generate Code
```bash
cd backend
go install github.com/sqlc-dev/sqlc/cmd/sqlc@latest
sqlc generate
```

This creates `internal/db/` with type-safe query functions.

### 2. Update Handlers
Replace GORM code with generated sqlc queries:

**Before (GORM)**:
```go
var items []models.Item
db.Where("project_id = ?", projectID).Find(&items)
```

**After (sqlc)**:
```go
items, err := queries.ListItemsByProject(ctx, projectID, limit, offset)
```

### 3. Update Server
Pass pgxpool instead of GORM db to handlers.

### 4. Test
```bash
go test ./... -v
```

## Benefits Summary

| Aspect | GORM | sqlc + pgx |
|--------|------|-----------|
| Complex Queries | ❌ Hard | ✅ Easy |
| Type Safety | ⚠️ Runtime | ✅ Compile-time |
| Performance | ⚠️ Overhead | ✅ Direct |
| Graph Queries | ❌ Limited | ✅ Full support |
| Explicit SQL | ❌ Hidden | ✅ Visible |
| Compliance | ⚠️ Opaque | ✅ Auditable |
| Learning Curve | ⚠️ Steep | ✅ Gentle |

## Conclusion

For TraceRTM's requirements:
- **60+ link types** across 12 categories
- **16 professional views** with complex relationships
- **Graph traversal** and recursive queries
- **1000+ concurrent agents**
- **Compliance and traceability** focus

**sqlc + pgx is the clear winner.** It's simpler, faster, and more explicit.

## References

- [SQLC_MIGRATION_GUIDE.md](./backend/SQLC_MIGRATION_GUIDE.md)
- [sqlc Documentation](https://docs.sqlc.dev/)
- [pgx Documentation](https://github.com/jackc/pgx)
- [PostgreSQL Recursive CTEs](https://www.postgresql.org/docs/current/queries-with.html)

