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October 28, 2022 12:39 pm GMT

JPA Repository - find by multiple Columns

In this tutorial, I will show you how to use JPA Repository to find by multiple fields example. At the end, you will know way to filter by multiple Columns using 3 ways: Derived Query, JPQL and Native Query.

This tutorial is originally from Bezkoder:
https://www.bezkoder.com/jpa-filter-by-multiple-columns/

Overview

For querying the data from the database with custom filter methods, Spring Data JPA support several ways:

  • Derived Query: JPA creates SQL queries based on the finder method and execute the query behind the scenes.
List<Tutorial> findAll();List<Tutorial> findByTitleContainingIgnoreCase(String title);
  • JPQL: inspired by SQL. It resemble SQL queries in syntax, but operate against JPA entity objects stored in a relational database rather than directly with database tables.
@Query("SELECT t FROM Tutorial t")List<Tutorial> findAll();@Query("SELECT t FROM Tutorial t WHERE t.published=true")List<Tutorial> findByPublished();
  • Native Query: actual SQL queries which can be operated directly with database object and tables.
@Query(value = "SELECT * FROM tutorials", nativeQuery = true)List<Tutorial> findAllNative();@Query(value = "SELECT * FROM tutorials t WHERE t.published=true", nativeQuery = true)List<Tutorial> findByPublishedNative();

For more details and examples about each kind, please visit:

Let's continue to create project that uses JPA Repository with find by multiple columns methods.

JPA filter by multiple columns

Technology

  • Java 8
  • Spring Boot 2 (with Spring Data JPA)
  • MySQL/PostgreSQL/H2 (embedded database)
  • Maven 3.8.1

Project Structure

jpa-findby-multiple-fields-example

Let me explain it briefly.

  • Tutorial data model class correspond to entity and table tutorials.
  • TutorialRepository is an interface that extends JpaRepository for filter/findby methods. It will be autowired in SpringBootQueryExampleApplication.
  • SpringBootQueryExampleApplication is SpringBootApplication which implements CommandLineRunner. We will use TutorialRepository to run Query methods here.
  • Configuration for Spring Datasource, JPA & Hibernate in application.properties.
  • pom.xml contains dependencies for Spring Boot and MySQL/PostgreSQL/H2 database.

Create & Setup Spring Boot project

Use Spring web tool or your development tool (Spring Tool Suite, Eclipse, Intellij) to create a Spring Boot project.

Then open pom.xml and add these dependencies:

<!-- web for access H2 database UI --><dependency>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-web</artifactId></dependency><dependency>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-data-jpa</artifactId></dependency>

We also need to add one more dependency.

  • If you want to use MySQL:
<dependency>    <groupId>mysql</groupId>    <artifactId>mysql-connector-java</artifactId>    <scope>runtime</scope></dependency>
  • or PostgreSQL:
<dependency>    <groupId>org.postgresql</groupId>    <artifactId>postgresql</artifactId>    <scope>runtime</scope></dependency>
  • or H2 (embedded database):
<dependency>    <groupId>com.h2database</groupId>    <artifactId>h2</artifactId>    <scope>runtime</scope></dependency>

Configure Spring Datasource, JPA, Hibernate

Under src/main/resources folder, open application.properties and write these lines.

  • For MySQL:
spring.datasource.url= jdbc:mysql://localhost:3306/testdb?useSSL=falsespring.datasource.username= rootspring.datasource.password= 123456spring.jpa.properties.hibernate.dialect= org.hibernate.dialect.MySQL5InnoDBDialect# Hibernate ddl auto (create, create-drop, validate, update)spring.jpa.hibernate.ddl-auto= update
  • For PostgreSQL:
spring.datasource.url= jdbc:postgresql://localhost:5432/testdbspring.datasource.username= postgresspring.datasource.password= 123spring.jpa.properties.hibernate.jdbc.lob.non_contextual_creation= truespring.jpa.properties.hibernate.dialect= org.hibernate.dialect.PostgreSQLDialect# Hibernate ddl auto (create, create-drop, validate, update)spring.jpa.hibernate.ddl-auto= update
  • spring.datasource.username & spring.datasource.password properties are the same as your database installation.
  • Spring Boot uses Hibernate for JPA implementation, we configure MySQL5InnoDBDialect for MySQL or PostgreSQLDialect for PostgreSQL
  • spring.jpa.hibernate.ddl-auto is used for database initialization. We set the value to update value so that a table will be created in the database automatically corresponding to defined data model. Any change to the model will also trigger an update to the table. For production, this property should be validate.
  • For H2 database:
spring.datasource.url=jdbc:h2:mem:testdbspring.datasource.driverClassName=org.h2.Driverspring.datasource.username=saspring.datasource.password=spring.jpa.show-sql=truespring.jpa.properties.hibernate.dialect=org.hibernate.dialect.H2Dialectspring.jpa.hibernate.ddl-auto= updatespring.h2.console.enabled=true# default path: h2-consolespring.h2.console.path=/h2-ui
  • spring.datasource.url: jdbc:h2:mem:[database-name] for In-memory database and jdbc:h2:file:[path/database-name] for disk-based database.
  • We configure H2Dialect for H2 Database
  • spring.h2.console.enabled=true tells the Spring to start H2 Database administration tool and you can access this tool on the browser: http://localhost:8080/h2-console.
  • spring.h2.console.path=/h2-ui is for H2 console's url, so the default url http://localhost:8080/h2-console will change to http://localhost:8080/h2-ui.

Create Entity

In model package, we define Tutorial class.

Tutorial has following fields: id, title, level, description, published, createdAt.

model/Tutorial.java

package com.bezkoder.spring.jpa.query.model;import javax.persistence.*;import java.util.Date;@Entity@Table(name = "tutorials")public class Tutorial {  @Id  @GeneratedValue(strategy = GenerationType.AUTO)  private long id;  private String title;  private String description;  private int level;  private boolean published;  @Temporal(TemporalType.TIMESTAMP)  private Date createdAt;  public Tutorial() {  }  public Tutorial(String title, String description, int level, boolean published, Date createdAt) {    this.title = title;    this.description = description;    this.level = level;    this.published = published;    this.createdAt = createdAt;  }  // getters and setters}
  • @Entity annotation indicates that the class is a persistent Java class.
  • @Table annotation provides the table that maps this entity.

  • @Id annotation is for the primary key.

  • @GeneratedValue annotation is used to define generation strategy for the primary key.

  • @Temporal annotation converts back and forth between timestamp and java.util.Date or time-stamp into time. For example, @Temporal(TemporalType.DATE) drops the time value and only preserves the date.

@Temporal(TemporalType.DATE)private Date createdAt;

JPA Repository Find by multiple Columns methods

Assume that we've already have tutorials table like this:

jpa-find-by-multiple-columns-example

Let's create a repository to interact with database.
In repository package, create TutorialRepository interface that extend JpaRepository.

repository/TutorialRepository.java

package com.bezkoder.spring.jpa.query.repository;import com.bezkoder.spring.jpa.query.model.Tutorial;public interface TutorialRepository extends JpaRepository<Tutorial, Long> {}

In this interface, we will write JPA Queries to filter data from database.

Findby multiple Fields using Derived Query

For multiple fields/multiple columns, we can use And, Or keywords between fields/columns.
Notice that you can concatenate as much And/Or as you want.

List<Tutorial> findByLevelAndPublished(int level, boolean isPublished);List<Tutorial> findByTitleOrDescription(String title, String description);

Result:

tutorials = tutorialRepository.findByLevelAndPublished(3, true);show(tutorials);/*Tutorial [id=1, title=Spring Data, description=Spring Data Description, level=3, published=true, createdAt=2022-03-11 00:00:00.0]Tutorial [id=3, title=Hibernate, description=Hibernate ORM Description, level=3, published=true, createdAt=2022-04-26 00:00:00.0]Tutorial [id=5, title=Spring JPA, description=Spring Data JPA Description, level=3, published=true, createdAt=2022-05-19 00:00:00.0]*/tutorials = tutorialRepository.findByTitleOrDescription("Hibernate", "Spring Data Description");show(tutorials);/*Tutorial [id=1, title=Spring Data, description=Spring Data Description, level=3, published=true, createdAt=2022-03-11 00:00:00.0]Tutorial [id=3, title=Hibernate, description=Hibernate ORM Description, level=3, published=true, createdAt=2022-04-26 00:00:00.0]*/

We can perform SQL LIKE query with following keywords:

  • Like: where x.field like param
  • NotLike: where x.field not like param
  • StartingWith: where x.field like %param (with appended %)
  • EndingWith: where x.field like param% (with prepended %)
  • Containing: where x.field like %param% (wrapped in %)

For case insensitive query, in SQL, we can force the value to all capital or lower case letters, then compare with the query values.
Spring JPA provide IgnoreCase keyword to do this with Derived Query.

List<Tutorial> findByTitleContainingIgnoreCase(String title);List<Tutorial> findByTitleContainingOrDescriptionContaining(String title, String description);List<Tutorial> findByTitleContainingIgnoreCaseAndPublished(String title, boolean isPublished);

Result:

tutorials = tutorialRepository.findByTitleContainingIgnoreCase("dat");show(tutorials);/*Tutorial [id=1, title=Spring Data, description=Spring Data Description, level=3, published=true, createdAt=2022-03-11 00:00:00.0]*/String text = "ot";tutorials = tutorialRepository.findByTitleContainingOrDescriptionContaining(text, text);show(tutorials);/*Tutorial [id=2, title=Java Spring Boot, description=Spring Framework Description, level=1, published=false, createdAt=2022-03-11 00:00:00.0]Tutorial [id=4, title=Spring Boot, description=Spring Boot Description, level=2, published=false, createdAt=2022-04-26 00:00:00.0]*/tutorials = tutorialRepository.findByTitleContainingAndPublished("ring", true);// or// tutorials = tutorialRepository.findByTitleContainingIgnoreCaseAndPublished("spring", true);show(tutorials);/*Tutorial [id=1, title=Spring Data, description=Spring Data Description, level=3, published=true, createdAt=2022-03-11 00:00:00.0]Tutorial [id=5, title=Spring JPA, description=Spring Data JPA Description, level=3, published=true, createdAt=2022-05-19 00:00:00.0]Tutorial [id=6, title=Spring Batch, description=Spring Batch Description, level=4, published=true, createdAt=2022-05-19 00:00:00.0]*/

Findby multiple Fields using JPQL

Let's use @Query annotation to create Spring JPA Query with SELECT and WHERE keywords.

@Query("SELECT t FROM Tutorial t WHERE LOWER(t.title) LIKE LOWER(CONCAT('%', :keyword,'%')) OR LOWER(t.description) LIKE LOWER(CONCAT('%', :keyword,'%'))")List<Tutorial> findByTitleContainingOrDescriptionContainingCaseInsensitive(String keyword);@Query("SELECT t FROM Tutorial t WHERE LOWER(t.title) LIKE LOWER(CONCAT('%', :title,'%')) AND t.published=:isPublished")List<Tutorial> findByTitleContainingCaseInsensitiveAndPublished(String title, boolean isPublished);

Result:

tutorials = tutorialRepository.findByTitleContainingOrDescriptionContainingCaseInsensitive("data");show(tutorials);/*Tutorial [id=1, title=Spring Data, description=Spring Data Description, level=3, published=true, createdAt=2022-03-11 00:00:00.0]Tutorial [id=5, title=Spring JPA, description=Spring Data JPA Description, level=3, published=true, createdAt=2022-05-19 00:00:00.0]*/tutorials = tutorialRepository.findByTitleContainingCaseInsensitiveAndPublished("spring", true);show(tutorials);/*Tutorial [id=1, title=Spring Data, description=Spring Data Description, level=3, published=true, createdAt=2022-03-11 00:00:00.0]Tutorial [id=5, title=Spring JPA, description=Spring Data JPA Description, level=3, published=true, createdAt=2022-05-19 00:00:00.0]Tutorial [id=6, title=Spring Batch, description=Spring Batch Description, level=4, published=true, createdAt=2022-05-19 00:00:00.0]*/

Findby multiple Fields using Native Query

We also use @Query annotation to create Spring JPA Native Query with SELECT and WHERE keywords.

@Query(value = "SELECT * FROM tutorials t WHERE LOWER(t.title) LIKE LOWER(CONCAT('%', :keyword,'%')) OR LOWER(t.description) LIKE LOWER(CONCAT('%', :keyword,'%'))", nativeQuery = true)List<Tutorial> findByTitleContainingOrDescriptionContainingCaseInsensitive(String keyword);@Query(value = "SELECT * FROM tutorials t WHERE LOWER(t.title) LIKE LOWER(CONCAT('%', :title,'%')) AND t.published=:isPublished", nativeQuery = true)List<Tutorial> findByTitleContainingCaseInsensitiveAndPublished(String title, boolean isPublished);

Result:

tutorials = tutorialRepository.findByTitleContainingOrDescriptionContainingCaseInsensitive("data");show(tutorials);/*Tutorial [id=1, title=Spring Data, description=Spring Data Description, level=3, published=true, createdAt=2022-03-11 00:00:00.0]Tutorial [id=5, title=Spring JPA, description=Spring Data JPA Description, level=3, published=true, createdAt=2022-05-19 00:00:00.0]*/tutorials = tutorialRepository.findByTitleContainingCaseInsensitiveAndPublished("spring", true);show(tutorials);/*Tutorial [id=1, title=Spring Data, description=Spring Data Description, level=3, published=true, createdAt=2022-03-11 00:00:00.0]Tutorial [id=5, title=Spring JPA, description=Spring Data JPA Description, level=3, published=true, createdAt=2022-05-19 00:00:00.0]Tutorial [id=6, title=Spring Batch, description=Spring Batch Description, level=4, published=true, createdAt=2022-05-19 00:00:00.0]*/

Run JPA Filter by Multiple Columns project

Let's open SpringJpaRepositoryQueryExampleApplication.java, we will implement CommandLineRunner and autowire TutorialRepository interface to run JPA Query methods here.

package com.bezkoder.spring.jpa.query;// import ...@SpringBootApplicationpublic class SpringJpaRepositoryQueryExampleApplication implements CommandLineRunner {  @Autowired  TutorialRepository tutorialRepository;  public static void main(String[] args) {    SpringApplication.run(SpringJpaRepositoryQueryExampleApplication.class, args);  }  @Override  public void run(String... args) throws Exception {    // call tutorialRepository methods here  }  private void show(List<Tutorial> tutorials) {    tutorials.forEach(System.out::println);  }}

Conclusion

Today we've known how to use JPA Repository to find by/filter by multiple columns in Spring Boot example using Derived Query, JPQL and Native Query.
We can query any number of fields separated by logical operators (AND, OR).

You can continue to write CRUD Rest APIs with:
Spring Boot, Spring Data JPA Rest CRUD API example

If you want to write Unit Test for the JPA Repository:
Spring Boot Unit Test for JPA Repository with @DataJpaTest

You can also know:

Happy learning! See you again.

Source Code

You can find the complete source code for this tutorial on Github that uses:

Further Reading

Fullstack CRUD App:

Associations:


Original Link: https://dev.to/tienbku/jpa-repository-find-by-multiple-columns-7nb

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