Question

我想使用Hibernate在MySql数据库中创建一个表，但是我无法使用代码来做到这一点。

App.java

package com.Hibernate;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

public class App {
    public static void main(String args[]) {
        Alien telusko = new Alien();
        telusko.setAid(10);
        telusko.setAname("Feind");
        telusko.setColor("Blue");

        Configuration con = new Configuration().configure().addAnnotatedClass(Alien.class);
        SessionFactory sf = con.buildSessionFactory(); 
        Session session =  sf.openSession();
        Transaction tx = session.beginTransaction();
        session.save(telusko);
        tx.commit();
    }

}

Alien.java

package com.Hibernate;

import javax.persistence.Entity;
import javax.persistence.Id;

@Entity
public class Alien {
    @Id
    private int aid;
    private String aname;
    private String color;
    public int getAid() { 
        return aid;
    }
    public void setAid(int aid) {
        this.aid = aid;
    }
    public String getAname() {
        return aname;
    }
    public void setAname(String aname) {
        this.aname = aname;
    }
    public String getColor() {
        return color;
    }
    public void setColor(String color) {
        this.color = color;
    }
}

Hibernate.cnf.xml

<?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.url">jdbc:mysql://localhost:3306/akash</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="hibernate.hbm2ddl.auto">create</property>
         <property name="show_sql">true</property>
    </session-factory>
</hibernate-configuration>

**由于无法创建表，但是当我手动将所需的表（即（Alien））创建到MySql中时，现在我的代码每次使用<propertyname="hibernate.hbm2ddl.auto">update</property>到Hibernate.cng.xml文件中更新表。 **

所以我无法解释为什么它不会自动创建表格并解决这个问题。**

很抱歉编写完整的代码

编辑
MyPrintStackTrace

Dec 03, 2019 8:33:08 PM org.hibernate.Version logVersion
INFO: HHH000412: Hibernate Core {5.4.5.Final}
Dec 03, 2019 8:33:14 PM org.hibernate.annotations.common.reflection.java.JavaReflectionManager <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {5.1.0.Final}
Dec 03, 2019 8:33:17 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
WARN: HHH10001002: Using Hibernate built-in connection pool (not for production use!)
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
Dec 03, 2019 8:33:17 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001005: using driver [com.mysql.jdbc.Driver] at URL [jdbc:mysql://localhost:3306/akash]
Dec 03, 2019 8:33:17 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001001: Connection properties: {user=root}
Dec 03, 2019 8:33:17 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001003: Autocommit mode: false
Dec 03, 2019 8:33:17 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl$PooledConnections <init>
INFO: HHH000115: Hibernate connection pool size: 20 (min=1)
Dec 03, 2019 8:33:18 PM org.hibernate.dialect.Dialect <init>
INFO: HHH000400: Using dialect: org.hibernate.dialect.MySQLDialect
Hibernate: drop table if exists Alien
Dec 03, 2019 8:33:22 PM org.hibernate.resource.transaction.backend.jdbc.internal.DdlTransactionIsolatorNonJtaImpl getIsolatedConnection
INFO: HHH10001501: Connection obtained from JdbcConnectionAccess [org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator$ConnectionProviderJdbcConnectionAccess@1f1cff6] for (non-JTA) DDL execution was not in auto-commit mode; the Connection 'local transaction' will be committed and the Connection will be set into auto-commit mode.
Hibernate: create table Alien (aid integer not null, aname varchar(255), color varchar(255), primary key (aid)) type=MyISAM
Dec 03, 2019 8:33:22 PM org.hibernate.resource.transaction.backend.jdbc.internal.DdlTransactionIsolatorNonJtaImpl getIsolatedConnection
INFO: HHH10001501: Connection obtained from JdbcConnectionAccess [org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator$ConnectionProviderJdbcConnectionAccess@1cff1b9] for (non-JTA) DDL execution was not in auto-commit mode; the Connection 'local transaction' will be committed and the Connection will be set into auto-commit mode.
Dec 03, 2019 8:33:22 PM org.hibernate.tool.schema.internal.ExceptionHandlerLoggedImpl handleException
WARN: GenerationTarget encountered exception accepting command : Error executing DDL "create table Alien (aid integer not null, aname varchar(255), color varchar(255), primary key (aid)) type=MyISAM" via JDBC Statement
org.hibernate.tool.schema.spi.CommandAcceptanceException: Error executing DDL "create table Alien (aid integer not null, aname varchar(255), color varchar(255), primary key (aid)) type=MyISAM" via JDBC Statement
    at org.hibernate.tool.schema.internal.exec.GenerationTargetToDatabase.accept(GenerationTargetToDatabase.java:67)
    at org.hibernate.tool.schema.internal.SchemaCreatorImpl.applySqlString(SchemaCreatorImpl.java:439)
    at org.hibernate.tool.schema.internal.SchemaCreatorImpl.applySqlStrings(SchemaCreatorImpl.java:423)
    at org.hibernate.tool.schema.internal.SchemaCreatorImpl.createFromMetadata(SchemaCreatorImpl.java:314)
    at org.hibernate.tool.schema.internal.SchemaCreatorImpl.performCreation(SchemaCreatorImpl.java:166)
    at org.hibernate.tool.schema.internal.SchemaCreatorImpl.doCreation(SchemaCreatorImpl.java:135)
    at org.hibernate.tool.schema.internal.SchemaCreatorImpl.doCreation(SchemaCreatorImpl.java:121)
    at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.performDatabaseAction(SchemaManagementToolCoordinator.java:156)
    at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.process(SchemaManagementToolCoordinator.java:73)
    at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:320)
    at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:462)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:708)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:724)
    at com.Hibernate.App.main(App.java:16)
Caused by: java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'type=MyISAM' at line 1
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:120)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
    at com.mysql.cj.jdbc.StatementImpl.executeInternal(StatementImpl.java:764)
    at com.mysql.cj.jdbc.StatementImpl.execute(StatementImpl.java:648)
    at org.hibernate.tool.schema.internal.exec.GenerationTargetToDatabase.accept(GenerationTargetToDatabase.java:54)
    ... 13 more

Dec 03, 2019 8:33:22 PM org.hibernate.engine.transaction.jta.platform.internal.JtaPlatformInitiator initiateService
INFO: HHH000490: Using JtaPlatform implementation: [org.hibernate.engine.transaction.jta.platform.internal.NoJtaPlatform]
Hibernate: insert into Alien (aname, color, aid) values (?, ?, ?)
Dec 03, 2019 8:33:23 PM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
WARN: SQL Error: 1146, SQLState: 42S02
Dec 03, 2019 8:33:23 PM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
ERROR: Table 'akash.alien' doesn't exist
Exception in thread "main" javax.persistence.PersistenceException: org.hibernate.exception.SQLGrammarException: could not execute statement
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:154)
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:181)
    at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:188)
    at org.hibernate.internal.SessionImpl.doFlush(SessionImpl.java:1362)
    at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:436)
    at org.hibernate.internal.SessionImpl.flushBeforeTransactionCompletion(SessionImpl.java:3235)
    at org.hibernate.internal.SessionImpl.beforeTransactionCompletion(SessionImpl.java:2403)
    at org.hibernate.engine.jdbc.internal.JdbcCoordinatorImpl.beforeTransactionCompletion(JdbcCoordinatorImpl.java:447)
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.beforeCompletionCallback(JdbcResourceLocalTransactionCoordinatorImpl.java:183)
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.access$300(JdbcResourceLocalTransactionCoordinatorImpl.java:40)
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl$TransactionDriverControlImpl.commit(JdbcResourceLocalTransactionCoordinatorImpl.java:281)
    at org.hibernate.engine.transaction.internal.TransactionImpl.commit(TransactionImpl.java:101)
    at com.Hibernate.App.main(App.java:20)
Caused by: org.hibernate.exception.SQLGrammarException: could not execute statement
    at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:63)
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:42)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:113)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:99)
    at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:200)
    at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:3208)
    at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:3722)
    at org.hibernate.action.internal.EntityInsertAction.execute(EntityInsertAction.java:91)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:604)
    at org.hibernate.engine.spi.ActionQueue.lambda$executeActions$1(ActionQueue.java:478)
    at java.util.LinkedHashMap.forEach(Unknown Source)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:475)
    at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:349)
    at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:40)
    at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:108)
    at org.hibernate.internal.SessionImpl.doFlush(SessionImpl.java:1358)
    ... 9 more
Caused by: java.sql.SQLSyntaxErrorException: Table 'akash.alien' doesn't exist
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:120)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeInternal(ClientPreparedStatement.java:953)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdateInternal(ClientPreparedStatement.java:1092)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdateInternal(ClientPreparedStatement.java:1040)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeLargeUpdate(ClientPreparedStatement.java:1340)
    at com.mysql.cj.jdbc.ClientPreparedStatement.executeUpdate(ClientPreparedStatement.java:1025)
    at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:197)
    ... 20 more

Answer 1

尝试以下方言。

org.hibernate.dialect.MySQL5InnoDBDialect

我遇到了类似的问题，以上解决方案对我来说很有效。如果这不起作用，请从日志中共享sql查询。

Answer 2

将MySql连接器jar从5.1升级到8.0可以解决此问题-我的代码不是问题。

无法使用Hibernate在数据库中创建表

2 个答案: