当数据库不为空时，我从 findAll Spring 数据和 h2 数据库中得到空列表

Question

我有一个带有 h2 数据库的 spring 启动 API 项目。我在 data.sql 中添加了一些数据，但是数据没有插入到数据库中，但是当我调用 findAll API 时，表创建成功，因为数据库表是空的，所以我得到一个空列表。

Application.properties

spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=password
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect

server.port=8888

data.sql

DROP TABLE IF EXISTS device;

DROP TABLE IF EXISTS gateway;

CREATE TABLE gateway (
    id INT AUTO_INCREMENT PRIMARY KEY,
    serial_number VARCHAR(250) UNIQUE,
    name VARCHAR(250),
    address VARCHAR(15) NOT NULL
);

CREATE TABLE device (
    id INT AUTO_INCREMENT PRIMARY KEY,
    UID INT UNIQUE,
    vendor VARCHAR(250),
    created DATE,
    status BOOLEAN,
    gateway_id INT,
    FOREIGN KEY (gateway_id) REFERENCES gateway(id)
);


INSERT INTO gateway (id, serial_number, name, address) VALUES (1,'GTW-1','Gateway 1','123.187.65.1');
INSERT INTO gateway (id, serial_number, name, address) VALUES (2,'GTW-2','Gateway 2','123.187.65.2');
INSERT INTO gateway (id, serial_number, name, address) VALUES (3,'GTW-3','Gateway 3','123.187.65.3');
INSERT INTO gateway (id, serial_number, name, address) VALUES (4,'GTW-4','Gateway 4','123.187.65.4');


INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (1,001,'huawei', parsedatetime('17-09-2012', 'dd-MM-yyyy'), true, 1);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (2,002,'intel', parsedatetime('11-07-2013', 'dd-MM-yyyy'), false, 1);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (3,003,'sony', parsedatetime('01-01-2015', 'dd-MM-yyyy'),true, 1);

INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (4,004,'sony', parsedatetime('17-09-2012', 'dd-MM-yyyy'),true, 2);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (5,005,'huawei', parsedatetime('11-10-2013', 'dd-MM-yyyy'),true, 2);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (6,006,'dell', parsedatetime('04-05-2010', 'dd-MM-yyyy'),true, 2);


INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (7,007,'sony', parsedatetime('13-09-2020', 'dd-MM-yyyy'),false, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (8,008,'dell', parsedatetime('05-09-2012', 'dd-MM-yyyy'),false, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (9,009,'intel', parsedatetime('12-12-2013', 'dd-MM-yyyy'),true, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (10,010,'dell', parsedatetime('17-07-2009', 'dd-MM-yyyy'),false, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (11,011,'sony', parsedatetime('15-05-2015', 'dd-MM-yyyy'),true, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (12,012,'toshiba', parsedatetime('09-09-2017', 'dd-MM-yyyy'),true, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (13,013,'intel', parsedatetime('10-10-2018', 'dd-MM-yyyy'),true, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (14,014,'dell', parsedatetime('11-11-2011', 'dd-MM-yyyy'),true, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (15,015,'sony', parsedatetime('01-06-2021', 'dd-MM-yyyy'),false, 3);
INSERT INTO device (id, UID, vendor, created, status, gateway_id) VALUES (16,016,'sony', parsedatetime('17-06-2012', 'dd-MM-yyyy'),true, 3);

Pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.3</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>gateways</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>gateways</name>
    <description>gateways</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-test</artifactId>
           <scope>test</scope>
        </dependency>


        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
        
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

主要Class

@SpringBootApplication
@EnableAutoConfiguration
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

}

Gateway.java

@Entity
@Table(name = "gateway")
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Gateway {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    
    @Column(name="serial_number", unique = true)
    private String serialNumber;
    
    @Column(name="name", unique = true)
    private String name;
    
    @Column(name="address")
    private String address;
    
    @OneToMany(mappedBy = "gateway")
    private List<Device> devices;
    
}

存储库

@Repository
public interface GatewayRepository extends JpaRepository<Gateway, Long>{

}

控制器

@CrossOrigin("*")
@RestController
@RequestMapping("/gateway")
public class GatewayController {

    @Autowired
    GatewayRepository gatewayRepository;
    
    @GetMapping()
    public ResponseEntity<List<Gateway>> getAllGateways() {
        try {
            List<Gateway> gateways = gatewayRepository.findAll();
            if (gateways.isEmpty()) {
                return new ResponseEntity<>(HttpStatus.NO_CONTENT);
            }
            return new ResponseEntity<>(gateways, HttpStatus.OK);
        } catch (Exception e) {
            return new ResponseEntity<>(null, HttpStatus.INTERNAL_SERVER_ERROR);
        }
    }
}

项目结构

Answer 1

将以下内容添加到您的应用程序属性以阻止 JPA 在您的 data.sql.

之上自动生成您的 gateway table

spring.jpa.hibernate.ddl-auto=none

顺便说一下，这是您 application.properties 中唯一需要的东西，因为其余的都是默认设置。

当数据库不为空时，我从 findAll Spring 数据和 h2 数据库中得到空列表

I get empty list from findAll Spring data and h2 data base while the database is not empty

java

h2

spring-data

spring-data-jpa

spring-boot