Column mapping with @Column in Spring Boot - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the database column name for the field.

Spring Boot

public class User {
    @Column(name = "[1]")
    private String username;
}

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

Auser_name

BuserName

Cusername

Duser-name

Attempts:

3 left

💡 Hint

Common Mistakes

Using the Java field name directly without matching the database column name.

Using camelCase instead of snake_case for column names.

The @Column(name = "user_name") annotation maps the username field to the user_name column in the database.

2fill in blank

medium

Complete the code to make the column non-nullable in the database.

Spring Boot

public class Product {
    @Column(name = "price", [1] = false)
    private Double price;
}

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

Aupdatable

Bnullable

Cinsertable

Dunique

Attempts:

3 left

💡 Hint

Common Mistakes

Using unique instead of nullable to control nullability.

Omitting the attribute and expecting non-null behavior.

The nullable = false attribute ensures the price column cannot be null in the database.

3fill in blank

hard

Fix the error in the annotation to set the column length to 100 characters.

Spring Boot

public class Employee {
    @Column(name = "email", length = [1])
    private String email;
}

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

A"100"

Bsize

Clength

D100

Attempts:

3 left

💡 Hint

Common Mistakes

Putting the number in quotes, which causes a type error.

Using incorrect attribute names like size.

The length attribute expects an integer value, so length = 100 is correct.

4fill in blank

hard

Fill both blanks to make the column unique and not nullable.

Spring Boot

public class Category {
    @Column(name = "category_name", [1] = true, [2] = false)
    private String categoryName;
}

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

Aunique

Bnullable

Cinsertable

Dupdatable

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing insertable or updatable with uniqueness or nullability.

Swapping the values true/false incorrectly.

Setting unique = true ensures no duplicate values, and nullable = false prevents null values.

5fill in blank

hard

Fill all three blanks to map the field with a custom column name, set length to 50, and make it non-updatable.

Spring Boot

public class Order {
    @Column(name = "[1]", length = [2], updatable = [3])
    private String orderCode;
}

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

Aorder_code

B50

Cfalse

Dtrue

Attempts:

3 left

💡 Hint

Common Mistakes

Using string quotes around the length number.

Setting updatable to true when it should be false.

The field is mapped to order_code column, limited to 50 characters, and cannot be updated after creation.