Finding and querying documents in Express - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to find all documents in a MongoDB collection using Express.

Express

app.get('/items', async (req, res) => {
  const items = await Item.[1]();
  res.json(items);
});

Drag options to blanks, or click blank then click option'

Afind

Binsert

Cupdate

Ddelete

Attempts:

3 left

💡 Hint

Common Mistakes

Using insert instead of find

Using update or delete which modify data

The find method retrieves all documents from the collection.

2fill in blank

medium

Complete the code to find documents matching a condition in Express.

Express

app.get('/users', async (req, res) => {
  const users = await User.find({ age: { [1]: 18 } });
  res.json(users);
});

Drag options to blanks, or click blank then click option'

A$lt

B$ne

C$gte

D$in

Attempts:

3 left

💡 Hint

Common Mistakes

Using $lt which means less than

Using $ne which means not equal

The $gte operator finds documents where age is greater than or equal to 18.

3fill in blank

hard

Fix the error in the code to find a single document by ID.

Express

app.get('/post/:id', async (req, res) => {
  const post = await Post.[1](req.params.id);
  res.json(post);
});

Drag options to blanks, or click blank then click option'

AfindOneById

BfindAllById

CfindByID

DfindById

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect method names like findOneById or findByID

Using findAllById which does not exist

The correct method to find a document by its ID is findById.

4fill in blank

hard

Fill both blanks to find documents where status is 'active' and sort by createdAt descending.

Express

const activeItems = await Item.find({ status: [1] }).[2]({ createdAt: -1 });

Drag options to blanks, or click blank then click option'

A'active'

Bsort

Cfilter

D'inactive'

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'inactive' instead of 'active'

Using 'filter' instead of 'sort' for ordering

We filter by status 'active' and then sort by createdAt descending using sort.

5fill in blank

hard

Fill all three blanks to find users older than 21, select only name and email fields, and limit results to 5.

Express

const users = await User.find({ age: { [1]: 21 } })
  .[2]('name email')
  .[3](5);

Drag options to blanks, or click blank then click option'

A$gt

Bselect

Climit

Dskip

Attempts:

3 left

💡 Hint

Common Mistakes

Using $gte instead of $gt

Using skip instead of limit

Not selecting fields properly

Use $gt to find age greater than 21, select to choose fields, and limit to restrict number of results.