@Query for custom JPQL in Spring Boot - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a custom JPQL query to find users by their email.

Spring Boot

public interface UserRepository extends JpaRepository<User, Long> {
    @Query("SELECT u FROM User u WHERE u.email = [1]")
    User findByEmail(String email);
}

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

A:email

B?1

Cemail

D?email

Attempts:

3 left

💡 Hint

Common Mistakes

Using positional parameters like ?1 instead of named parameters.

Omitting the colon before the parameter name.

The correct syntax for named parameters in JPQL is :parameterName. Here, :email matches the method parameter email.

2fill in blank

medium

Complete the code to write a JPQL query that selects users with age greater than a given value.

Spring Boot

public interface UserRepository extends JpaRepository<User, Long> {
    @Query("SELECT u FROM User u WHERE u.age [1] :age")
    List<User> findUsersOlderThan(int age);
}

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

A<

B<=

C=

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using < instead of >.

Using = which would select users with exact age.

The query should select users whose age is greater than the given parameter, so the operator is >.

3fill in blank

hard

Fix the error in the JPQL query to correctly select users by their last name ignoring case.

Spring Boot

public interface UserRepository extends JpaRepository<User, Long> {
    @Query("SELECT u FROM User u WHERE LOWER(u.lastName) = [1]")
    List<User> findByLastNameIgnoreCase(String lastName);
}

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

ALOWER(:lastName)

B:lastName.toLowerCase()

ClastName.toLowerCase()

D:lastName

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to call Java methods on parameters inside JPQL.

Not using the colon for named parameters.

JPQL supports the LOWER() function on parameters as well. To compare ignoring case, apply LOWER() to the parameter :lastName.

4fill in blank

hard

Fill both blanks to write a JPQL query that selects users whose first name starts with a given prefix.

Spring Boot

public interface UserRepository extends JpaRepository<User, Long> {
    @Query("SELECT u FROM User u WHERE u.firstName [1] :prefix")
    List<User> findByFirstNameStartingWith([2] prefix);
}

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

ALIKE

BString

Cint

D=

Attempts:

3 left

💡 Hint

Common Mistakes

Using = instead of LIKE for pattern matching.

Using int type for a string prefix parameter.

The JPQL operator for pattern matching is LIKE. The method parameter type for a prefix string is String.

5fill in blank

hard

Fill all three blanks to write a JPQL query that selects users with age between two values.

Spring Boot

public interface UserRepository extends JpaRepository<User, Long> {
    @Query("SELECT u FROM User u WHERE u.age BETWEEN [1] AND [2]")
    List<User> findUsersBetweenAges([3] minAge, [3] maxAge);
}

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

A:minAge

B:maxAge

Cint

DString

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting colons before parameter names in JPQL.

Using String type for age parameters.

The JPQL BETWEEN clause uses named parameters :minAge and :maxAge. The method parameters for ages should be of type int.