<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration
   PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN"
   "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
   <session-factory>
      <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
      <property name="connection.url">jdbc:mysql://127.0.0.1/learnHiberDB</property>
      <property name="connection.username">root</property>
      <property name="connection.password">root</property>
      <property name="show_sql">true</property>
      <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
      <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>

        <mapping package="learn_hiber.chapter4"/>
        <mapping class="learn_hiber.chapter4.Author"/>
        <mapping class="learn_hiber.chapter4.Book"/>
        <mapping class="learn_hiber.chapter4.ComputerBook"/>
        <mapping class="learn_hiber.chapter4.Publisher"/>


     
   </session-factory>
</hibernate-configuration>

Exception in thread "main" org.hibernate.HibernateException: The dialect was not set. Set the property hibernate.dialect.
        at org.hibernate.dialect.Dialect.getDialect(Dialect.java:635)
        at org.hibernate.dialect.Dialect.getDialect(Dialect.java:657)
        at org.hibernate.tool.hbm2ddl.SchemaExport.<init>(SchemaExport.java:84)
        at org.hibernate.tool.hbm2ddl.SchemaExport.<init>(SchemaExport.java:59)
        at learn_hiber.chapter4.GenerateSchema.main(GenerateSchema.java:25)

package learn_hiber.chapter4;

import java.io.File;
import java.io.IOException;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.tool.hbm2ddl.SchemaExport;

public class GenerateSchema
{
public String printURL(){
   
    return this.getClass().getResource("/learn_hiber/hibernate.cfg.xml").getPath();
}
    public static void main(String[] args)
    {
        GenerateSchema gn = new GenerateSchema();
       
       // Amended to allow a path (to the hibernate.cfg.xml) to
       // be passed to the configuration.
        AnnotationConfiguration cfg = ExampleConfiguration.getConfig();;
       
        System.out.println(gn.printURL());
        cfg.addFile(new File(gn.printURL()));
        SchemaExport schemaExport = new SchemaExport(cfg);
        schemaExport.create(true, true);
    }
}