How to Query Nested Properties in Spring Data MongoDB?

How can I retrieve a list of Student objects based on a property of a nested Student object in Spring Data MongoDB?

public List<Student> findByStudentGradesClassName(final String className);

In Spring Data MongoDB, querying nested properties can sometimes lead to confusion, especially when dealing with lists of objects. If you're encountering an error regarding parameter types, it's important to understand how to properly structure your query method to retrieve the expected data.

@Query("{ 'student.grades.className': ?0 }")
List<Student> findByStudentGradesClassName(String className);

Causes

• The method signature is incorrect; Spring Data requires a specific naming convention to recognize how to query nested fields.
• The underlying data structure may not support direct String-based queries for properties within nested lists.

Solutions

• Modify your repository method to use the correct naming convention by leveraging the Spring Data derived query methods.
• Ensure that you properly construct your query to accommodate the nested structure.

Mistake: Using a method signature that doesn't conform to Spring Data's naming conventions.

Solution: Use derived query methods or the @Query annotation to form proper MongoDB queries.

Mistake: Assuming Spring Data can handle nested lists without additional configuration.

Solution: Utilize MongoDB query language to explicitly state how to match against nested lists.