Query builder in NestJS - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a query builder for the User entity.

NestJS

const userQuery = dataSource.getRepository(User).[1]();

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

Adelete

Bfind

Csave

DcreateQueryBuilder

Attempts:

3 left

💡 Hint

Common Mistakes

Using repository methods like find or save instead of createQueryBuilder.

The createQueryBuilder method starts building a query for the User entity.

2fill in blank

medium

Complete the code to add a WHERE clause filtering users by age.

NestJS

const users = await userQuery.where('user.age [1] :age', { age: 18 }).getMany();

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

A>=

B=

C<=

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' which filters only age exactly 18.

Using '<=' which filters age less than or equal to 18.

The operator >= filters users with age 18 or older.

3fill in blank

hard

Fix the error in the code to select only the 'name' and 'email' fields.

NestJS

const users = await userQuery.select(['user.name', [1]]).getMany();

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

A'name'

B'user.email'

C'user.age'

D'email'

Attempts:

3 left

💡 Hint

Common Mistakes

Using field names without alias like 'email' causes errors.

Selecting wrong fields like 'name' again or 'user.age'.

Fields must be prefixed with the alias 'user.', so 'user.email' is correct.

4fill in blank

hard

Fill both blanks to order users by creation date descending and limit results to 5.

NestJS

const users = await userQuery.orderBy('user.createdAt', [1]).[2](5).getMany();

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

A'DESC'

B'ASC'

Climit

Dtake

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'ASC' instead of 'DESC' for descending order.

Using 'limit' instead of 'take' which is the correct method.

Use 'DESC' to order descending and take(5) to limit results in NestJS query builder.

5fill in blank

hard

Fill all three blanks to build a query that filters active users, selects their id and name, and orders by name ascending.

NestJS

const users = await userQuery.where('user.isActive = [1]').select(['user.[2]', 'user.[3]']).orderBy('user.name', 'ASC').getMany();

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

Atrue

Bid

Cname

Dfalse

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'false' instead of 'true' for active filter.

Selecting wrong fields or missing alias prefix.

Filter active users with true, select id and name fields, and order by name ascending.