---
name: typeorm-schema-optimizer
description: Optimize TypeORM entities for performance, query efficiency, migration safety, and relationship design — analyze decorators, indexes, eager loading, and connection pooling.
metadata:
  tags: ["typeorm", "orm", "database", "typescript", "optimization"]
---

# TypeORM Schema Optimizer

Analyze TypeORM entities for performance issues, query inefficiencies, missing indexes, relationship design problems, and migration risks. Use when reviewing TypeORM schemas, optimizing slow queries, or preparing for production scale.

## Usage

```
"Optimize my TypeORM entities"
"Check for N+1 queries in my TypeORM code"
"Audit TypeORM indexes and relations"
"Review migration safety for TypeORM changes"
```

## How It Works

### 1. Entity Discovery

```bash
# Find all TypeORM entities
grep -rn "@Entity\|@ViewEntity\|@ChildEntity" src/ | head -20
# Find repositories
grep -rn "extends Repository\|@InjectRepository\|getRepository" src/ | head -20
# Check TypeORM config
cat ormconfig.json 2>/dev/null || cat data-source.ts 2>/dev/null
```

### 2. Schema Analysis

**Column optimization:**
- Column types match actual data requirements
- Unnecessary `nullable: true` on required fields
- Missing `length` on string columns (default is VARCHAR(255) — wasteful or too short?)
- Enum columns using string instead of native enum type
- JSON columns where structured columns would be more queryable
- Missing default values for common patterns

**Index analysis:**
- Columns used in WHERE clauses without indexes
- Composite indexes for multi-column queries
- Covering indexes for SELECT-heavy queries
- Unique constraints for business rules
- Partial indexes for filtered queries
- Index on foreign key columns (TypeORM doesn't auto-create)

**Relationship design:**
- `eager: true` on relationships (loads every time, often unnecessary)
- Missing `cascade` options where needed
- Circular eager loading (infinite loops)
- `@ManyToMany` without join table customization
- Missing `onDelete` behavior (default is no action)
- Polymorphic relationships using discriminators correctly

### 3. Query Performance

- N+1 detection in repository methods
- Missing `leftJoinAndSelect` where data is accessed post-query
- `find` with deep relations instead of query builder
- Missing pagination on list queries
- Raw queries bypassing TypeORM benefits
- Transaction usage for multi-step writes

### 4. Connection & Pool

- Connection pool size appropriate for workload
- Idle connection timeout configured
- Read replicas configured for read-heavy workloads
- Connection error handling and retry logic
- Logging level appropriate for environment

### 5. Migration Safety

- Entity changes that generate destructive migrations
- Column type changes that lose data
- Index changes that lock tables
- Relationship changes that break foreign keys

## Output

```
## TypeORM Schema Analysis

**Entities:** 18 | **Relations:** 24 | **Indexes:** 12

### 🔴 Critical (3)
1. **Eager loading loop** — User → Posts (eager) → Author (eager) → Posts...
   → Remove `eager: true` from at least one side

2. **Missing index on FK** — Order.userId has no index
   With 500K orders, joins on userId cause full table scans
   → Add `@Index()` on `userId` column

3. **N+1 in getOrders()** — orders.service.ts:34
   Loads orders then iterates to access `order.items` individually
   → Use `relations: ['items']` or query builder with join

### 🟡 Improvements (4)
4. 6 entities with `eager: true` — performance risk at scale
5. VARCHAR(255) on `status` fields — use enum type (4 possible values)
6. Missing `onDelete: 'CASCADE'` on child entities
7. No read replica configured (DB CPU at 80%)

### ✅ Good Practices
- Proper use of table inheritance for payment types
- Transaction wrapping for order creation flow
- Soft delete with `@DeleteDateColumn`
```


---
Source attribution: LeoYeAI
Original project: https://github.com/LeoYeAI/openclaw-master-skills/blob/e5199b56ae1ff72e141586c17695563486c46702/skills/typeorm-schema-optimizer/SKILL.md
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Dave AI.

## Upstream license notice

MIT License

Copyright (c) 2026 MyClaw.ai (LeoYeAI)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.



# Dave AI resource metadata

Creator / publisher: LeoYeAI
Original project: https://github.com/LeoYeAI/openclaw-master-skills/blob/e5199b56ae1ff72e141586c17695563486c46702/skills/typeorm-schema-optimizer/SKILL.md
Attribution basis: Source repository record

Fields of work: Development & Engineering, Product Management
Roles: Backend Developer, Data Engineer, Database Administrator, ML / AI Engineer, Product Manager
Specialties: Backend, Database
Tools: Typeorm, Typescript
Country applicability: Country not specified
Classification basis: Source catalog labels
Instruction SHA-256: 2bb079399f4bdb3872945d4e61ea8693c41d75b438cc469f49d9441f9a0ef4f4