Question

我对春博特+金塔瓦利卡塔基斯纳塔基斯加基斯群岛的基本处理有问题。

将所有表格的栏目与QueryDSL相提并重,并将试验清单退回

        QRoles roles = QRoles.roles;
        List<Roles> roleList = sqlQueryFactory.select(roles)
                            .from(roles)
                            .fetch();
        logger.debug(roleList.toString());

2023/06/29 22:38:43 ERROR [http-nio-8080-exec-10] - Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: org.springframework.jdbc.BadSqlGrammarException: null; bad SQL grammar [select roles
from roles]] with root cause
java.sql.SQLSyntaxErrorException: Unknown column  roles  in  field list 
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:121)
SQLError.java:121
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
SQLExceptionsMapping.java:122
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:916)
ClientPreparedStatement.java:916
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeQuery(ClientPreparedStatement.java:972)
ClientPreparedStatement.java:972
    at com.zaxxer.hikari.pool.ProxyPreparedStatement.executeQuery(ProxyPreparedStatement.java:52)
ProxyPreparedStatement.java:52
    at com.zaxxer.hikari.pool.HikariProxyPreparedStatement.executeQuery(HikariProxyPreparedStatement.java)
    at com.querydsl.sql.AbstractSQLQuery.fetch(AbstractSQLQuery.java:445)
AbstractSQLQuery.java:445
    at com.example.demo.service.LoginUserDetailsService.listing(LoginUserDetailsService.java:88)

<>strong>bad-> 选定角色

the SQL I expected -> select roles.* from roles

pom.xml >>

<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>3.1.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>17</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>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>com.querydsl</groupId>
            <artifactId>querydsl-apt</artifactId>
            <classifier>jakarta</classifier>
            <version>5.0.0</version>
        </dependency>
        <dependency>
            <groupId>com.querydsl</groupId>
            <artifactId>querydsl-jpa</artifactId>
            <classifier>jakarta</classifier>
            <version>5.0.0</version>
        </dependency>
        <dependency>
            <groupId>com.querydsl</groupId>
            <artifactId>querydsl-sql</artifactId>
            <version>5.0.0</version>
        </dependency>
        <dependency>
            <groupId>com.querydsl</groupId>
            <artifactId>querydsl-sql-spring</artifactId>
            <version>${querydsl.version}</version>
        </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>

pom.xml <<

bash-4.4# echo $JAVA_HOME
/usr/java/openjdk-17
bash-4.4# java -version
openjdk version "17.0.2" 2022-01-18
OpenJDK Runtime Environment (build 17.0.2+8-86)
OpenJDK 64-Bit Server VM (build 17.0.2+8-86, mixed mode, sharing)

ash-4.4# mysql --version
mysql  Ver 8.0.33 for Linux on aarch64 (MySQL Community Server - GPL)

bash-4.4# "/app/demo/mvnw" spring-boot:run -f "/app/demo/pom.xml"
2023/06/29 22:38:21 INFO  [restartedMain] - Starting DemoApplication using Java 17.0.2 with PID 35542 (/app/demo/target/classes started by root in /app)
2023/06/29 22:38:21 DEBUG [restartedMain] - Running with Spring Boot v3.1.1, Spring v6.0.10
2023/06/29 22:38:21 INFO  [restartedMain] - The following 1 profile is active: "dev"
2023/06/29 22:38:22 INFO  [restartedMain] - Bootstrapping Spring Data JPA repositories in DEFAULT mode.

mysql> show create table roles;
CREATE TABLE `roles` (
  `id` int NOT NULL AUTO_INCREMENT,
  `name` varchar(32) COLLATE utf8mb4_unicode_ci NOT NULL,
  `created_by` varchar(255) COLLATE utf8mb4_unicode_ci NOT NULL,
  `created_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
  `updated_by` varchar(255) COLLATE utf8mb4_unicode_ci NOT NULL,
  `updated_at` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci

作用。

package com.example.demo.Entity;

import java.time.LocalDateTime;

import com.querydsl.core.annotations.QueryEntity;

import jakarta.persistence.Entity;
import jakarta.persistence.Id;
import jakarta.persistence.Table;
import lombok.Data;

@Entity
@Table(schema = Roles.SCHEMA_NAME, name = Roles.TABLE_NAME)
@Data
@QueryEntity
public class Roles {
    public static final String SCHEMA_NAME = "sample_schema";
    public static final String TABLE_NAME  = "roles";
    @Id
    private Integer id;
    private String  name;
    private String createdBy;
    private LocalDateTime createdAt;
    private String updatedBy;
    private LocalDateTime updatedAt;
}

作用。

Q作用。

package com.example.demo.Entity;

import static com.querydsl.core.types.PathMetadataFactory.*;

import com.querydsl.core.types.dsl.*;

import com.querydsl.core.types.PathMetadata;
import javax.annotation.processing.Generated;
import com.querydsl.core.types.Path;


/**
 * QRoles is a Querydsl query type for Roles
 */
@Generated("com.querydsl.codegen.DefaultEntitySerializer")
public class QRoles extends EntityPathBase<Roles> {

    private static final long serialVersionUID = 14135660L;

    public static final QRoles roles = new QRoles("roles");

    public final DateTimePath<java.time.LocalDateTime> createdAt = createDateTime("createdAt", java.time.LocalDateTime.class);

    public final StringPath createdBy = createString("createdBy");

    public final NumberPath<Integer> id = createNumber("id", Integer.class);

    public final StringPath name = createString("name");

    public final DateTimePath<java.time.LocalDateTime> updatedAt = createDateTime("updatedAt", java.time.LocalDateTime.class);

    public final StringPath updatedBy = createString("updatedBy");

    public QRoles(String variable) {
        super(Roles.class, forVariable(variable));
    }

    public QRoles(Path<? extends Roles> path) {
        super(path.getType(), path.getMetadata());
    }

    public QRoles(PathMetadata metadata) {
        super(Roles.class, metadata);
    }

}

Q作用。

QuerydslSql QueryConfig.java >>

package com.example.demo.config;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;

import com.querydsl.jpa.JPQLQueryFactory;
import com.querydsl.jpa.impl.JPAQueryFactory;
import com.querydsl.sql.Configuration;
import com.querydsl.sql.MySQLTemplates;
import com.querydsl.sql.SQLQueryFactory;
import com.querydsl.sql.SQLTemplates;
import com.querydsl.sql.spring.SpringConnectionProvider;
import com.querydsl.sql.spring.SpringExceptionTranslator;

import jakarta.persistence.EntityManager;

@org.springframework.context.annotation.Configuration
public class QuerydslSqlQueryConfig {

    @Autowired
    private DataSource dataSource;

    @Autowired
    private EntityManager entityManager;

    @Bean
    public Configuration configuration() {
        SQLTemplates templates = MySQLTemplates.builder().build();
        Configuration configuration = new Configuration(templates);
        configuration.setExceptionTranslator(new SpringExceptionTranslator());
        return configuration;
    }

    @Bean
    public JPQLQueryFactory jpaQueryFactory() {
        return new JPAQueryFactory(entityManager);
    }

    @Bean
    public SQLQueryFactory sqlQueryFactory() {
        return new SQLQueryFactory(configuration(), new SpringConnectionProvider(dataSource));
    }

}

QuerydslSql QueryConfig.java <<

LoginUserDetailsservice.java >>

@Service
public class LoginUserDetailsService {
    @Autowired
    SQLQueryFactory sqlQueryFactory;

    @Transactional
    public AccountListingResponseModel listing() {
        QRoles roles = QRoles.roles;
        List<Roles> roleList = sqlQueryFactory.select(roles)
                            .from(roles)
                            .fetch();  // <-- error line
        logger.debug(roleList.toString());
        ...
     }

b. Log。

Do you know what is causing this? please help me

Uploaded sample source to GitHub https://github.com/Elendira/hello_querydsl/tree/v.1.0.1/demo/src/main/java/com/example/demo https://github.com/Elendira/hello_querydsl/releases/tag/v.1.0.1

-- Elen

Answer 1

当你打电话sql QueryFactory.select(roles)时,我们根本不知道需要从表格中选择所有栏目。你们需要从贵格朗斯的物体中选择每一个领域,而不是(或利用某些教训),从而试图改变你们的疑虑:

List<Roles> roleList = jpaQueryFactory.selectFrom(roles).fetch();

或者说:

List<Roles> roleList = sqlQueryFactory.select(
        roles.id, roles.name, roles.createdBy, roles.createdAt, roles.updatedBy, roles.updatedAt)
    .from(roles)
    .fetch();

友情链接