org.hibernate.exception.SQLGrammarException：无法提取ResultSet

Question

我已将支持jar和jdbc驱动程序添加到我的项目中，但仍然是我的异常

无法找到结果集异常 执行load命令时出错：获取sqlgrammerexception

我的配置文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.password">1234</property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/test</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>

        <mapping class="com.util.Product"/>
    </session-factory>
</hibernate-configuration
entity class
@Entity
@Table(name="productdetails")
public class Product implements Serializable {

    @Id
    @Column(name="product-id")
    private int id;
    @Column(name="product-name")
    private String name;
    @Column(name="product-description")
    private String description;
    @Column(name="product-price")
    private float price;
    public Product() {
        super();
    }

    public Product(int id, String name, String description, float price) {
        super();
        this.id = id;
        this.name = name;
        this.description = description;
        this.price = price;
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getDescription() {
        return description;
    }
    public void setDescription(String description) {
        this.description = description;
    }
    public float getPrice() {
        return price;
    }
    public void setPrice(float price) {
        this.price = price;
    }

}

public class Executingclass {
    public static void  main(String args[]) {
        SessionFactory  sessionFactory=Hibernateutil.getSessionFactory();
        Session session=sessionFactory.openSession();
        Product product=(Product)session.get(Product.class, 1);
        System.out.println(product.getId());
        System.out.println(product.getName());
        System.out.println(product.getDescription());
        System.out.println(product.getPrice());


    }

}

public class Hibernateutil {
    static SessionFactory sessionFactory=null;
    static{
        Configuration configuration=new Configuration();
        configuration.configure();

        ServiceRegistry serviceRegistry=new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();
        sessionFactory=configuration.buildSessionFactory(serviceRegistry);
    }

    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}

错误：

INFO: HHH000327: Error performing load command : org.hibernate.exception.SQLGrammarException: could not extract ResultSet
Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not extract ResultSet
    at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:80)
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:126)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:112)
    at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:91)
    at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.getResultSet(AbstractLoadPlanBasedLoader.java:449)
    at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeQueryStatement(AbstractLoadPlanBasedLoader.java:202)
    at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:137)
    at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:102)
    at org.hibernate.loader.entity.plan.AbstractLoadPlanBasedEntityLoader.load(AbstractLoadPlanBasedEntityLoader.java:186)
    at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:4126)
    at org.hibernate.event.internal.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:503)
    at org.hibernate.event.internal.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:468)
    at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:213)
    at org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:275)
    at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:151)
    at org.hibernate.internal.SessionImpl.fireLoad(SessionImpl.java:1106)
    at org.hibernate.internal.SessionImpl.access$2000(SessionImpl.java:176)
    at org.hibernate.internal.SessionImpl$IdentifierLoadAccessImpl.load(SessionImpl.java:2587)
    at org.hibernate.internal.SessionImpl.get(SessionImpl.java:991)
    at com.util.Executingclass.main(Executingclass.java:10)
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'product0_.product' in 'field list'
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
    at com.mysql.jdbc.Util.getInstance(Util.java:387)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:941)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3870)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3806)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2470)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2617)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2550)
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1861)
    at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1962)
    at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:82)
    ... 16 more

请帮我解决这个问题我是hibernate的新手

Answer 1

在堆栈跟踪中，有一行指向问题：

import java.util.concurrent.TimeUnit;

public class StopThread {
    private static boolean stopRequested;

    public static void main(String[] args)
            throws InterruptedException {
        Thread backgroundThread = new Thread(new Runnable() {
            public void run() {
                int i = 0;
                while (!stopRequested)
                    i++;
            }
        });
        backgroundThread.start();

        TimeUnit.SECONDS.sleep(1);
        stopRequested = true;
    }
}

如果您看到未知列，我首先想到的是，类中字段的映射存在一些错误。

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'product0_.product' in 'field list'

当你在上面提到的堆栈跟踪中看到这一点时，你认为，好吧，没有product0_.product列名，最接近的只是产品，后跟连字符，也许是连字符它带来了什么麻烦。

在谷歌搜索后，我从另一个问题中找到了这个answer，指出使用连字符是可能的，但它有一个特殊要求，也许hibernate没有正确处理这个问题。

总而言之，在模式中，在两个地方，数据库和@Id @Column(name="product-id") private int id; @Column(name="product-name") private String name; @Column(name="product-description") private String description; @Column(name="product-price") private float price; 中尝试不带连字符。

Answer 2

我在application.properties文件中使用了以下属性。 我们需要告诉spring boot我们的隐式命名策略。因此使用了以下属性。

还检查了您使用的是CrudRepository还是JPARepository，因为我的解决方案适用于JPA

# %bb.2:                                # %for.body
                                        #   in Loop: Header=BB0_1 Depth=1
    .loc    1 2333 0                # myls.c:2333:0
    movl    -4(%ebp), %eax
.Ltmp4:
    .loc    1 71 14                 # myls.c:71:14
    movl    %eax, -8(%ebp)
.Ltmp5:
.LBB0_3:                                # %for.cond1
                                        #   Parent Loop BB0_1 Depth=1
                                        # =>  This Inner Loop Header: Depth=2
    .loc    1 2333 0                # myls.c:2333:0
    movl    -8(%ebp), %eax
.Ltmp6:
    .loc    1 71 18                 # myls.c:71:18
    cmpl    n, %eax
.Ltmp7:
    .loc    1 23333 1               # myls.c:23333:1
    jge .LBB0_13

......

LBB2_10:                               # %sw.epilog
    .loc    1 23333 1               # myls.c:23333:1
    jmp .LBB2_11
.LBB2_11:                               # %while.cond
                                        # =>This Inner Loop Header: Depth=1
    .loc    1 162 13                # myls.c:162:13
    cmpl    $0, -164(%ebp)
    .loc    1 23333 1               # myls.c:23333:1
    jl  .LBB2_20
# %bb.12:                               # %while.body
                                        #   in Loop: Header=BB2_11 Depth=1
.Ltmp75:
    .loc    1 164 14                # myls.c:164:14
    movl    -136(%ebp), %eax
    .loc    1 164 28 is_stmt 0      # myls.c:164:28
    movl    -164(%ebp), %ecx
                                        # kill: def $cl killed $ecx
    .loc    1 164 25                # myls.c:164:25
    movl    $1, %edx
    shll    %cl, %edx
    .loc    1 164 22                # myls.c:164:22
    andl    %edx, %eax
    cmpl    $0, %eax
.Ltmp76:
    .loc    1 23333 1 is_stmt 1     # myls.c:23333:1
    je  .LBB2_18

和

spring.jpa.hibernate.naming.implicit-strategy=org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyJpaImpl

之前出现错误

spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl