Java e bancos de dados: uma visão geral de bibliotecas e APIs

Convidamos futuros alunos do curso "Java Developer. Professional" e todos os interessados ​​a participar da aula aberta sobre o tema "Introdução ao Spring Data Jdbc" .



E agora estamos compartilhando a tradução tradicional de material útil.

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Este artigo fornece uma visão geral de bibliotecas e APIs populares para trabalhar com bancos de dados em Java, incluindo JDBC, Hibernate, JPA, jOOQ, Spring Data e muito mais.

Java e bancos de dados: uma introdução

Cada vez que você precisa interagir com bancos de dados, surgem três perguntas:

• Qual abordagem de desenvolvimento deve ser usada: java-first ou database-first? Escreva classes Java ou consultas SQL primeiro? O banco de dados existente será usado?

  
  
  
  
  

• SQL-: CRUD- (select from, insert into, update where), ?

  
  
  
  
  

• - (object-relational mapping, ORM)? Java / ?

  
  
  
  
  

- :

public class User {

    private Integer id;

    private String firstName;

    private String lastName;

    // Constructor/Getters/Setters....

}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

USERS, :

Java- ?

:

1. JDBC — .

   
   
   
   
   

2. SQL-, jOOQ Spring JDBC.

   
   
   
   
   

3. ORM, Hibernate JPA. 

   
   
   
   
   

, JDBC. ? , Spring Hibernate, JDBC.

JDBC:

JDBC?

Java — JDBC API (Java Database Connectivity). , , JDBC . , , SQL-, JDBC . 

JDBC , , JDBC JDK / JRE. JDBC- . 

, JDBC, , SQL-, What is JDBC?  (" JDBC?") . 

JDBC

, Users, , , , List<User>



— Java.

: JDBC SQL Java- ( ). :

package com.marcobehler;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

public class JdbcQueries {

    public static void main(String[] args) throws SQLException {
        try (Connection conn = DriverManager
                .getConnection("jdbc:mysql://localhost/test?serverTimezone=UTC",
                        "myUsername", "myPassword")) {

            PreparedStatement selectStatement = conn.prepareStatement("select * from users");
            ResultSet rs = selectStatement.executeQuery();

            List<User> users = new ArrayList<>();

            while (rs.next()) { // will traverse through all rows
                Integer id = rs.getInt("id");
                String firstName = rs.getString("first_name");
                String lastName = rs.getString("last_name");

                User user = new User(id, firstName, lastName);
                users.add(user);
            }

        }
    }
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

:

try (Connection conn = DriverManager
        .getConnection("jdbc:mysql://localhost/test?serverTimezone=UTC",
                "myUsername", "myPassword")) {
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

MySQL. DriverManager.getConnection



try-with-resources, , .

PreparedStatement selectStatement = conn.prepareStatement("select * from users");
ResultSet rs = selectStatement.executeQuery();
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

SQL- PreparedStatement



. (PreparedStatement



?



, .)

List<User> users = new ArrayList<>();

while (rs.next()) { // will traverse through all rows
    Integer id = rs.getInt("id");
    String firstName = rs.getString("first_name");
    String lastName = rs.getString("last_name");

    User user = new User(id, firstName, lastName);
    users.add(user);
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

ResultSet



( , SQL-), Java, ResultSet



(getString()



, getInt()



).

( ) :

• SQL- (: select * from USERS where name = ? and registration_date = ?
  
  
  
  ). SQL-.

  
  
  
  
  

• , , . 

  
  
  
  
  

, JDBC : SQL Java .

JDBC

JDBC " ". SQL JDBC, SQL- Java. .

, .

ORM-: Hibernate, JPA

Java-, , Java, SQL. java-first, , Java-, . 

, , - : Java- ( )? Java- ( , ). 

ORM, Hibernate JPA.

Hibernate?

Hibernate — ORM- (Object-Relational Mapping, - ), 2001 (!). 5.4.X, 6.x .

Hibernate , :

1. () java- - , .

   
   
   
   
   

2. SQL- CRUD-, , .

   
   
   
   
   

3. (HQL, Criteria API) SQL. , "-" SQL.

   
   
   
   
   

, . , , , , , JDBC.

create table users (
    id integer not null,
    first_name varchar(255),
    last_name varchar(255),
    primary key (id)
)
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Java.

public class User {

        private Integer id;

        private String firstName;

        private String lastName;

        //Getters and setters are omitted for brevity
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, hibernate-core.jar . Hibernate, User.java



Users? Hibernate.

Hibernate

Hibernate , . User.java



Invoices () Users ()?

xml-. xml-, .

, @Entity, @Column @Table. , User.java



, , .

import javax.persistence.Entity;
import javax.persistence.Table;
import javax.persistence.GeneratedValue;
import javax.persistence.Column;
import javax.persistence.Id;

@Entity
@Table(name="users")
public static class User {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    @Column(name="first_name")
    private String firstName;

    @Column(name="last_name")
    private String lastName;

        //Getters and setters are omitted for brevity
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, :

1. @Entity — Hibernate, .

   
   
   
   
   

2. @Table — Hibernate, .

   
   
   
   
   

3. @Column — Hibernate, .

   
   
   
   
   

4. @Id @GeneratedValue — Hibernate, .

   
   
   
   
   

, , . Hibernate , .

Hibernate (5.x)

Hibernate. , Hibernate, SessionFactory



, .

SessionFactory



Session



. Session, , ( , JDBC-) . Session SQL / HQL / Criteria — .

Hibernate.

Hibernate (> 5.x) , Spring . Hibernate, .

public static void main(String[] args) {
    // Hibernate specific configuration class
    StandardServiceRegistryBuilder standardRegistry
        = new StandardServiceRegistryBuilder()
            .configure()
            .build();

    // Here we tell Hibernate that we annotated our User class
    MetadataSources sources = new MetadataSources( standardRegistry );
    sources.addAnnotatedClass( User.class );
    Metadata metadata = metadataSources.buildMetadata();

    // This is what we want, a SessionFactory!
    SessionFactory sessionFactory = metadata.buildSessionFactory();
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

.

Hibernate

, SessionFactory



, Session



(, ) SessionFactory



, , , . 

Hibernate / JPA "persistence" (, ), Java . , , : , .. SQL INSERT ().

, SQL : Hibernate .

Session session = sessionFactory.openSession();
User user = new User();
user.setFirstName("Hans");
user.setLastName("Dampf");
// this line will generate and execute the "insert into users" sql for you!
session.save( user );
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

JDBC PreparedStatement



, Hibernate , SQL ( !).

, SQL- (select



, update



delete



).

// Hibernate generates: "select from users where id = 1"
User user = session.get( User.class, 1 );

// Hibernate generates: "update users set...where id=1"
session.update(user);

// Hibernate generates: "delete from useres where id=1"
session.delete(user);
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Hibernate Query Language (HQL)

, User



. , SQL-. Hibernate , HQL (Hibernate Query Language).

HQL SQL, Java- . , HQL- (MySQL, Oracle, Postgres . .), , .

, "HQL Java-"? :

List<User> users = session.createQuery("select from User u where u.firstName = 'hans'", User.class).list();

session.createQuery("update User u set u.lastName = :newName where u.lastName = :oldName")
            .executeUpdate();
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

SQL-, , (first_name



), (u.firstName



) User.java



! Hibernate HQL SQL . SELECT User.

HQL HQL Hibernate.

Criteria API

HQL- , , ( IDE, IntelliJ). — HQL / SQL ( WHERE ).

Hibernate — Criteria API. Criteria API (1 2), . 1 - Hibernate 6.x, , 2.

Criteria API (v2) . " " . .

, HQL Criteria API.

CriteriaBuilder builder = entityManager.getCriteriaBuilder();
CriteriaQuery<User> criteria = builder.createQuery( User.class );
Root<User> root = criteria.from( User.class );
criteria.select( root );
criteria.where( builder.equal( root.get( User_.firstName ), "hans" ) );
List<User> users = entityManager.createQuery( criteria ).getResultList();
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, . , if-else



where



.

, "select * from users where firstName =?



" .

Hibernate

Hibernate , . . Hibernate : , (lazy load), . , - .

:

1. , "Hibernate - , " - . , , Hibernate.

   
   
   
   
   

2. , Hibernate SQL. , , SQL Hibernate' SQL- .

   
   
   
   
   

: Hibernate SQL.

Hibernate?

"Java Persistence with Hibernate". 608 , Hibernate. Hibernate.

, (Vlad Mihalcea) (Thorben Janssen). Hibernate .

, Hibernate . , Hibernate.

Java Persistence API (JPA)?

Hibernate, JPA? Hibernate?

JPA — , . JPA , , JPA. JPA, , Hibernate, EclipseLink TopLink.

, , , , (, Criteria API . .) ., JPA-.

, , Hibernate EclipseLink, JPA- . JPA- (Hibernate) , . , JPA — Hibernate.

JPA

• JPA 1.0 — 2006 .

  
  
  
  
  

• JPA 2.0 — 2009 .

  
  
  
  
  

• JPA 2.1 — 2013 .

  
  
  
  
  

• JPA 2.2 — 2017 .

  
  
  
  
  

, , Vlad Mihalcea Thorben Janssen .

Hibernate JPA?

JPA , persistance- (Hibernate, EclipseLink ..) .

JPA Hibernate, JPA Hibernate. , JPQL — HQL . JPQL HQL, .

, JPA , — , , , , Hibernate. Hibernate, EclipseLink TopLink .

: JPA Hibernate?

, , :

• JPA Hibernate- , JPA.

  
  
  
  
  

• Hibernate ( ).

  
  
  
  
  

JPA

JPA , , EntityManagerFactory



, EntityManager



.

, JDBC Hibernate API. JPA API.

EntityManagerFactory factory = Persistence.createEntityManagerFactory( "org.hibernate.tutorial.jpa" );

EntityManager entityManager = factory.createEntityManager();
entityManager.getTransaction().begin();
entityManager.persist( new User( "John Wayne") );
entityManager.persist( new User( "John Snow" ) );
entityManager.getTransaction().commit();
entityManager.close();
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

(persist save, EntityManager Session), , Hibernate.

Hibernate, :

package org.hibernate;

public interface Session extends SharedSessionContract, EntityManager, HibernateEntityManager, AutoCloseable {
  // methods
}

// and

public interface SessionFactory extends EntityManagerFactory, HibernateEntityManagerFactory, Referenceable, Serializable, java.io.Closeable {
    // methods
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

:

• Hibernate SessionFactory — JPA EntityManagerFactory

  
  
  
  
  

• Hibernate Session — JPA EntityManager

  
  
  
  
  

.

JPQL

, JPA — JPQL. , HQL (Hibernate), JPQL HQL, .

, :

// HQL
int updatedEntities = session.createQuery(
        "update Person " +
        "set name = :newName " +
        "where name = :oldName" )
.setParameter( "oldName", oldName )
.setParameter( "newName", newName )
.executeUpdate();

// JPQL
int updatedEntities = entityManager.createQuery(
        "update Person p " +
        "set p.name = :newName " +
        "where p.name = :oldName" )
.setParameter( "oldName", oldName )
.setParameter( "newName", newName )
.executeUpdate();
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Criteria API JPA

HQL JPQL, Criteria API JPA Criteria API Hibernate. Criteria API Hibernate .

JPA?

JPA , Hibernate. EclipseLink (. Hibernate vs Eclipselink) ( ) TopLink.

Hibernate , . , BatooJPA. , JPA .

, , , . Hibernate, , 2020 .

QueryDSL

, QueryDSL, JPA? HQL / JPQL (.. ), Criteria API (2.0).

QueryDSL : Criteria API, .

, QueryDSL - , 2020 , . JPQ, NoSQL , MongoDB Lucene.

QueryDSL, SQL  "select * from users where first_name =: name"

QUser user = QUser.user;
JPAQuery<?> query = new JPAQuery<Void>(entityManager);
List<User> users = query.select(user)
  .from(user)
  .where(user.firstName.eq("Hans"))
  .fetch();
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

QUser



? QueryDSL User



, JPA / Hibernate, , .

. JPA Criteria 2.0?

ORM- Java:

ORM- — . — , - JPA SQL.

, , ORM . , , . 

, , Hibernate, SQL .

SQL-:  

, , , (database-first), ORM, Java (java-first).

, () Java-.

jOOQ

jOOQ — (Lukas Eder). , SQL, Java.

, jOOQ :

1. Java, , jOOQ.

   
   
   
   
   

2. SQL- JDBC .

   
   
   
   
   

3. jOOQ SQL, .

   
   
   
   
   

, , jOOQ Users, . jOOQ USERS , :

// "select u.first_name, u.last_name, s.id from USERS u inner join SUBSCRIPTIONS s
// on u.id = s.user_id where u.first_name = :name"
Result<Record3<String, String, String>> result =
create.select(USERS.FIRST_NAME, USERS.LAST_NAME, SUBSCRIPTIONS.ID)
      .from(USERS)
      .join(SUBSCRIPTIONS)
      .on(USERS.SUBSCRIPTION_ID.eq(SUBSCRIPTIONS.ID))
      .where(USERS.FIRST_NAME.eq("Hans"))
      .fetch();
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

jOOQ SQL- , CRUD-, POJO .

( , pivot, flashback-, OLAP, , ).

jOOQ.

MyBatis

MyBatis — database-first. MyBatis — IBATIS 3.0, Apache Attic.

MyBatis SQLSessionFactory ( SessionFactory Hibernate). SQLSessionFactory SQL- . SQL- XML, .

:

package org.mybatis.example;
public interface UserMapper {
  @Select("SELECT * FROM users WHERE id = #{id}")
  User selectUser(int id);
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

XML-:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
  PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="org.mybatis.example.UserMapper">
  <select id="selectUser" resultType="User">
    select * from users where id = #{id}
  </select>
</mapper>

      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

:

UserMapper mapper = session.getMapper(UserMapper.class);
User user = mapper.selectUser(1);
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

MyBatis , User. , , , . XML- .

MyBatis SQL, , , XML SQL- (- if-else-when SQL-).

Jdbi

Jdbi — JDBC, . SQL-. API .

-, Fluent API:

Jdbi jdbi = Jdbi.create("jdbc:h2:mem:test"); // (H2 in-memory database)

List<User> users = jdbi.withHandle(handle -> {
    handle.execute("CREATE TABLE user (id INTEGER PRIMARY KEY, name VARCHAR)");

    // Named parameters from bean properties
    handle.createUpdate("INSERT INTO user(id, name) VALUES (:id, :name)")
            .bindBean(new User(3, "David"))
            .execute();

    // Easy mapping to any type
    return handle.createQuery("SELECT * FROM user ORDER BY name")
            .mapToBean(User.class)
            .list();
});
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

-, API:

// Define your own declarative interface
public interface UserDao {
    @SqlUpdate("CREATE TABLE user (id INTEGER PRIMARY KEY, name VARCHAR)")
    void createTable();

    @SqlUpdate("INSERT INTO user(id, name) VALUES (:id, :name)")
    void insertBean(@BindBean User user);

    @SqlQuery("SELECT * FROM user ORDER BY name")
    @RegisterBeanMapper(User.class)
    List<User> listUsers();
}

public class MyApp {
    public static void main(String[] args) {
        Jdbi jdbi = Jdbi.create("jdbc:h2:mem:test");
        jdbi.installPlugin(new SqlObjectPlugin());

        List<User> userNames = jdbi.withExtension(UserDao.class, dao -> {
            dao.createTable();
            dao.insertBean(new User(3, "David"));
            return dao.listUsers();
        });
    }
}

      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

fluent-jdbc

fluent-jdbc — , Jdbi. JDBC. .

FluentJdbc fluentJdbc = new FluentJdbcBuilder()
        .connectionProvider(dataSource)
        .build();

Query query = fluentJdbc.query();

query
        .update("UPDATE CUSTOMER SET NAME = ?, ADDRESS = ?")
        .params("John Doe", "Dallas")
        .run();

List<Customer> customers = query.select("SELECT * FROM CUSTOMER WHERE NAME = ?")
        .params("John Doe")
        .listResult(customerMapper);
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

SimpleFlatMapper

SimpleFlatMapper , , ResultSet JDBC Record jOOQ POJO. , " " , , JDBC, jOOQ, queryDSL, JDBI Spring JDBC.

JDBC:

// will map the resultset to User POJOs
JdbcMapper<DbObject> userMapper =
    JdbcMapperFactory
        .newInstance()
        .newMapper(User.class)


try (PreparedStatement ps = con.prepareStatement("select * from USERS")) {
    ResultSet rs = ps.executeQuery());
    userMapper.forEach(rs, System.out::println);  //prints out all user pojos
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Spring JDBC Spring Data

Spring , Spring Data, Spring.

Spring JDBC Template

JDBCTemplate



— Spring (, spring-jdbc). 2001 , Spring Data JDBC.

JDBC- ResultSet, , , @Transactional- Spring.

: JdbcTemplate



NamedParameterJdbcTemplate



. , , .

// plain JDBC template with ? parameters

JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);

jdbcTemplate.execute("CREATE TABLE users(" +
            "id SERIAL, first_name VARCHAR(255), last_name VARCHAR(255))"); (1)

jdbcTemplate.batchUpdate("INSERT INTO users(first_name, last_name) VALUES (?,?)", Arrays.asList("john", "wayne"));  (2)

jdbcTemplate.query(
            "SELECT id, first_name, last_name FROM users WHERE first_name = ?", new Object[] { "Josh" },
            (rs, rowNum) -> new User(rs.getLong("id"), rs.getString("first_name"), rs.getString("last_name"))
    ).forEach(user -> log.info(user.toString()));   (3)

// named JDBC template with :named parameters

NamedParameterJdbcTemplate namedTemplate = new NamedParameterJdbcTemplate(datasource);

SqlParameterSource namedParameters = new MapSqlParameterSource().addValue("id", 1);
namedParameterJdbcTemplate.queryForObject(              (4)
  "SELECT * FROM USERS WHERE ID = :id", namedParameters, String.class);
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

1. SQL . , JDBC SQLException, Spring RuntimeException
   
   
   
   .

   
   
   
   
   

2. (?
   
   
   
   ) .

   
   
   
   
   

3. RowMapper
   
   
   
   JDBC ResultSet POJO .

   
   
   
   
   

4. NamedParameterJdbcTemplate
   
   
   
   SQL- (, :id
   
   
   
   ), (?
   
   
   
   ).

   
   
   
   
   

, , JdbcTemplate



JDBC API.

Spring

Spring — @Transactional.

, , , Hibernate, jOOQ JPA, .

JPA, EntityManager (, EntityManager — Hibernate Session, JDBC ).

EntityManagerFactory factory = Persistence.createEntityManagerFactory( "org.hibernate.tutorial.jpa" );

EntityManager entityManager = factory.createEntityManager();
entityManager.getTransaction().begin();
entityManager.persist( new Event( "Our very first event!", new Date() ) );
entityManager.persist( new Event( "A follow up event", new Date() ) );
entityManager.getTransaction().commit();
entityManager.close();
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Spring Hibernate / JPA :

@PersistenceContext
private EntityManager entityManager;

@Transactional
public void doSomeBusinessLogic() {
    entityManager.persist( new Event( "Our very first event!", new Date() ) );
    entityManager.persist( new Event( "A follow up event", new Date() ) );
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, . , , .

, Java Database Connections & Transactions (" Java"). , .

Spring Data JPA

, Spring Data, " Spring , ". , Fortune 500. ?

Spring Data — :

1. , : Spring Data JDBC Spring Data JPA.

   
   
   
   
   

2. , Spring Data REST, Spring Data Redis Spring Data LDAP. -.

   
   
   
   
   

Spring Data JDBC Spring Data JPA?

Spring Data /DAO SQL-. ( , .)

: —   /DAO .

User.java



, UserRepository



. UserRepository



, findByEmail



, findById



. . , SQL- Users.

User user = userRepository.findByEmail("my@email.com")
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Spring Data , JPA- User (@Entity, @Column, @Table ..) ! , CRUD- (save, delete, findBy) .

Spring Data JPA- 

. , classpath



spring-data-{jdbc|jpa}.jar



. :

import org.springframework.data.jpa.repository.JpaRepository;
import com.marcobehler.domain.User;

public interface MyUserRepository extends JpaRepository<User, Long> {

    // JpaRepository contains all of these methods, you do not have to write them yourself!

        List<T> findAll();

        List<T> findAll(Sort sort);

        List<T> findAllById(Iterable<ID> ids);

        <S extends T> List<S> saveAll(Iterable<S> entities);

    // and many more...that you can execute without implementing, because Spring Data JPA will
    // automatically generate an implementation for you - at runtime
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

JpaRepository



Spring Data ( , JPA), find



/save



( ), JpaRepository



( ).

Spring Data JPA / JDBC

, JPA ( SQL), . , , Ruby on Rails. 

import org.springframework.data.jpa.repository.JpaRepository;
import com.marcobehler.domain.User;

public interface MyUserRepository extends JpaRepository<User, Long> {

  List<User> findByEmailAddressAndLastname(String emailAddress, String lastname);
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Spring . SQL: "select * from Users where email_address = :emailAddress and lastName = :lastName



".

Spring Data JDBC ( CrudRepository



). .

import org.springframework.data.repository.CrudRepository;
import org.springframework.data.jdbc.repository.Query;
import com.marcobehler.domain.User;

public interface MyUserRepository extends CrudRepository<User, Long> {

  @Query("select * from Users where email = :emailAddress and lastName = :lastName ")
  List<User> findByEmailAddressAndLastname(@Param("emailAddress") String emailAddress, @Param("lastName") String lastname);
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Spring Data JPA ( @Query , ). - .

import org.springframework.data.jpa.repository.Query;

public interface MyUserRepository extends JpaRepository<User, Long> {
    @Query("select u from User u where u.emailAddress = ?1")
    User findByEmailAddress(String emailAddress);
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Spring Data:

:

1. Spring Data — , , . javax.persistence DAO.

   
   
   
   
   

2. Spring Data JPA — JPA / Hibernate. , , , . Spring Data JPA - JPA-, ORM.

   
   
   
   
   

3. Spring Data JDBC — JDBC. JDBC, ORM (, , …). .

   
   
   
   
   

, Spring Data Spring- Spring Boot-.

, , Spring Data, .

. . ( , , , ):

• , , , SQL ( java-). 

  
  
  
  
  

• , .

  
  
  
  
  

• , .. 608 .

  
  
  
  
  

• Hibernate, Hibernate, JPA.

  
  
  
  
  

• jOOQ database-first .

  
  
  
  
  

• . , JPA- jOOQ JDBC. , QueryDSL.

  
  
  
  
  

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"Java Developer. Professional".



" Spring Data Jdbc".

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