QueryTrace

Detects ORM code patterns (Prisma, SQLAlchemy, ActiveRecord) that will cause N+1 queries or missing indexes. Flags them inline before you ever run the code.

Features

• 10 Detection Patterns for common N+1 query problems

• Multi-ORM Support:

  • Prisma (TypeScript/JavaScript)
  • SQLAlchemy (Python)
  • ActiveRecord (Ruby)
  • Sequelize (JavaScript)
  • TypeORM (TypeScript)
  • Django ORM (Python)
  • Flask-SQLAlchemy (Python)

• Inline Diagnostics: Problems appear as squiggly underlines with explanations

• Performance Hints: Suggests fixes like include(), select_related(), or eager_load()

• Zero Configuration: Works out of the box

Usage

Automatic Scanning

QueryTrace automatically scans open files as you type. No commands needed.

Command Palette

• QueryTrace: Scan Current File — Manually trigger a scan
• QueryTrace: Toggle Scanning — Enable/disable QueryTrace diagnostics

How It Works

QueryTrace looks for patterns like:

• Looping over query results and making nested queries inside the loop
• Accessing relations without eager loading
• Filtering in loops instead of in the database query

Configuration

{
  "queryTrace.enabled": true,
  "queryTrace.orms": [
    "prisma",
    "sqlalchemy",
    "activerecord",
    "sequelize",
    "typeorm"
  ],
  "queryTrace.severity": "warning"
}

Example

Problematic Code (N+1):

const users = await prisma.user.findMany();
for (const user of users) {
  const posts = await prisma.post.findMany({
    where: { authorId: user.id }
  });
}

QueryTrace Diagnostic:

⚠ Potential N+1 query: Querying inside a loop.
Consider using `include: { posts: true }` in the initial query.

Fixed Code:

const users = await prisma.user.findMany({
  include: { posts: true }
});
for (const user of users) {
  console.log(user.posts);
}

Supported ORMs

• Prisma — .findMany(), .findFirst(), nested loops
• SQLAlchemy — .query(), .filter(), lazy loading
• ActiveRecord — .where(), .find(), N+1 in loops
• Sequelize — .findAll(), nested queries
• TypeORM — .find(), relations without eager loading
• Django ORM — .filter(), select_related() hints
• Flask-SQLAlchemy — .query.all() in loops

Requirements

• VS Code 1.85.0 or higher

License

MIT