Performance

// Before: full collection scan
await users.find({ email: "alice@example.com" }).toArray();

// After: indexed lookup
await users.createIndex({ email: 1 });
await users.find({ email: "alice@example.com" }).toArray();

// Bad: loads entire collection
const all = await users.find({}).toArray();

// Good: paginated
const page = await users.find({}).limit(20).skip(0).toArray();

// Bad: returns full documents
const users = await users.find({}).toArray();

// Good: returns only needed fields
const names = await users.find({}).project({ name: 1, email: 1 }).toArray();

// Bad: multiple write operations
for (const user of users) {
  await collection.insertOne(user);
}

// Good: single write operation
await collection.insertMany(users);

// Bad: replaces entire document
await users.updateOne(
  { _id: "123" },
  { name: "Alice", email: "new@example.com", ...allOtherFields }
);

// Good: updates specific fields
await users.updateOne({ _id: "123" }, { $set: { email: "new@example.com" } });

toollessdb compact mydb users

toollessdb stats mydb users

Collection: users
Documents: 1,500
File size: 2.4 MB
Dead ratio: 15%