스파르타 부트캠프 Query Method (다락방)

JPA Query Method는 메서드 이름을 통해서 쿼리를 자동 생성한다.

 

메서드 이름은

 

특정 키워드와 규칙을 따르고

Spring Data JPA는

이를 해석하여 적절한 

JPQL(Java Persistence Query Language)쿼리를 생성한다.

 

메소드 생성규칙

(find, delete, count, exists) By + 접두사 - 키워드 - 필드이름으로

시작해야한다.

 

Optional<Entity> findByField(Objects fieldName);

void deleteByField(Objects fieldName);

long countByField(Objects fieldName);

boolean existsByField(Objects fieldName)

Keyword	Sample	snippet
Distinct	findDistinctByLastnameAndFirstname	select distinct …​ where x.lastname = ?1 and x.firstname = ?2
And	findByLastnameAndFirstname	… where x.lastname = ?1 and x.firstname = ?2
Or	findByLastnameOrFirstname	… where x.lastname = ?1 or x.firstname = ?2
Is, Equals	findByFirstname,findByFirstnameIs,findByFirstnameEquals	… where x.firstname = ?1
Between	findByStartDateBetween	… where x.startDate between ?1 and ?2
LessThan	findByAgeLessThan	… where x.age < ?1
LessThanEqual	findByAgeLessThanEqual	… where x.age <= ?1
GreaterThan	findByAgeGreaterThan	… where x.age > ?1
GreaterThanEqual	findByAgeGreaterThanEqual	… where x.age >= ?1
After	findByStartDateAfter	… where x.startDate > ?1
Before	findByStartDateBefore	… where x.startDate < ?1
IsNull, Null	findByAge(Is)Null	… where x.age is null
IsNotNull, NotNull	findByAge(Is)NotNull	… where x.age is not null
Like	findByFirstnameLike	… where x.firstname like ?1
NotLike	findByFirstnameNotLike	… where x.firstname not like ?1
StartingWith	findByFirstnameStartingWith	… where x.firstname like ?1 (parameter bound with appended %)
EndingWith	findByFirstnameEndingWith	… where x.firstname like ?1 (parameter bound with prepended %)
Containing	findByFirstnameContaining	… where x.firstname like ?1 (parameter bound wrapped in %)
OrderBy	findByAgeOrderByLastnameDesc	… where x.age = ?1 order by x.lastname desc
Not	findByLastnameNot	… where x.lastname <> ?1
In	findByAgeIn(Collection<Age> ages)	… where x.age in ?1
NotIn	findByAgeNotIn(Collection<Age> ages)	… where x.age not in ?1
True	findByActiveTrue()	… where x.active = true
False	findByActiveFalse()	… where x.active = false

 

https://hs-backend.tistory.com/203

스파르타 부트캠프 연관관계 맵핑 (다락방)