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创建邮管局联系实体的数据库表
原标题:Create database tables from eclipse link JPA entities

I want to deploy my Java application to Heroku, I m using eclipse link JPA.

为此,我需要通过 Java制作表格,但到目前为止,我只想到下面的代码,但我如何让DDL编制表格。 我拿着用于发展的MySQL,而Heroku是用于生产的邮政。 因此,我想提出表格说明,以考虑到这一点。

import javax.persistence.*;

public class SchemaCreator
{
  public static void main(String[] args)
  {
    EntityManagerFactory factory =
    Persistence.createEntityManagerFactory("bitcoin");
    EntityManager em = factory.createEntityManager();

    String ddl = /// <--- How do I get it ?

    em.createNativeQuery(ddl);
  }
}
问题回答

缩略语

如果加上我坚持不懈的话,我会说:

<property name="eclipselink.ddl-generation" value="drop-and-create-tables"/>
<property name="eclipselink.ddl-generation.output-mode" value="database"/> 

然后,如果某个实体尚未进入数据库,我将先访问一个实体。





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