<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
version="2.0">
<persistence-unit name="org.hibernate.jpa">
<properties>
<property name="jakarta.persistence.jdbc.url" value="jdbc:mysql:///sql-dsl"/>
<property name="jakarta.persistence.jdbc.driver" value="com.mysql.cj.jdbc.Driver"/>
<property name="jakarta.persistence.jdbc.password" value="root"/>
<property name="jakarta.persistence.jdbc.user" value="root"/>
<property name="hibernate.hbm2ddl.auto" value="update"/>
<property name="hibernate.format_sql" value="true"/>
<property name="hibernate.show_sql" value="true"/>
<property name="hibernate.jdbc.batch_size" value="10000"/>
<property name="hibernate.physical_naming_strategy"
value="org.hibernate.boot.model.naming.CamelCaseToUnderscoresNamingStrategy"/>
</properties>
</persistence-unit>
</persistence><?xml version="1.0" encoding="UTF-8"?>
<configuration>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"/>
</configuration>SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
-- ----------------------------
-- Table structure for company
-- ----------------------------
DROP TABLE IF EXISTS `company`;
CREATE TABLE `company` (
`id` int(11) NOT NULL,
`addr` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
`name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;
-- ----------------------------
-- Records of company
-- ----------------------------
INSERT INTO `company` VALUES (1, 'ShangHai', 'Microsoft');
-- ----------------------------
-- Table structure for employee
-- ----------------------------
DROP TABLE IF EXISTS `employee`;
CREATE TABLE `employee` (
`id` int(11) NOT NULL,
`age` int(11) NULL DEFAULT NULL,
`company_id` int(11) NULL DEFAULT NULL,
`name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
PRIMARY KEY (`id`) USING BTREE,
INDEX `FK2yuxsfrkkrnkn5emoobcnnc3r`(`company_id`) USING BTREE,
CONSTRAINT `FK_company_id` FOREIGN KEY (`company_id`) REFERENCES `company` (`id`) ON DELETE RESTRICT ON UPDATE RESTRICT
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;
-- ----------------------------
-- Records of employee
-- ----------------------------
INSERT INTO `employee` VALUES (1, 18, 1, 'Luna');
SET FOREIGN_KEY_CHECKS = 1;package github.alittlehuang.sql4j.example;
import github.alittlehuang.sql4j.dsl.expression.path.Persistable;
import jakarta.persistence.Entity;
import jakarta.persistence.Id;
import lombok.Data;
@Data
@Entity
public class Company implements Persistable {
@Id
private Integer id;
private String name;
private String addr;
}package github.alittlehuang.sql4j.example;
import jakarta.persistence.*;
import lombok.Data;
@Data
@Entity
public class Employee {
@Id
private Integer id;
private String name;
private Integer age;
private Integer companyId;
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "companyId", updatable = false, insertable = false)
private Company company;
}package github.alittlehuang.sql4j.example;
import github.alittlehuang.sql4j.dsl.QueryBuilder;
import github.alittlehuang.sql4j.dsl.builder.Query;
import github.alittlehuang.sql4j.jpa.JpaQueryBuilder;
import jakarta.persistence.EntityManager;
import jakarta.persistence.EntityManagerFactory;
import jakarta.persistence.Persistence;
public class Example {
public static void main(String[] args) {
try (EntityManagerFactory factory = Persistence.createEntityManagerFactory("org.hibernate.jpa")) {
EntityManager em = factory.createEntityManager();
QueryBuilder builder = new JpaQueryBuilder(em);
Query<Employee> query = builder.query(Employee.class);
runExample(query);
}
}
private static void runExample(Query<Employee> query) {
// select * from employee where id = 1
query.where(Employee::getId).eq(1).getSingle();
// select employee.*, company.* from
// employee left join company
// on employee.company_id = company.id
// where employee.id = 1
query.where(Employee::getId).eq(1)
.fetch(Employee::getCompany)
.getSingle();
// select * from employee where name = 'Luna' and age > 10
query.where(Employee::getName).eq("Luna")
.and(Employee::getAge).gt(10)
.getList();
// select * from employee where name = 'Luna' and age > 10 order by id desc limit 0,100
query.where(Employee::getName).eq("Luna")
.and(Employee::getAge).gt(10)
.orderBy(Employee::getId).desc()
.getList(0, 100);
// select employee.* from
// employee left join company
// on employee.company_id = company.id
// where company.name = 'Microsoft'
query.where(Employee::getCompany).to(Company::getName).eq("Microsoft").getList();
}
}