如何在JPA中将数据库用作数据库源 [英] How to use a database as your database source in JPA

问题描述

我是JBoss开发应用程序的新手，因此我专门制作了Ticket Monster的教程。现在，我已经创建了一个Event JPA Entity，并且在运行中，它表明我可以保存一个事件。但是，当我重新启动计算机时，似乎我保存的事件已丢失，因此研究它并找到有关内存数据库的一些信息。我的问题是如何告诉/配置我的项目不使用内存数据库，而是使用典型的数据库，所以每次重新启动计算机时数据都在数据库中。我想将PostgreSQL用于我的数据库。我当前设置为JPA的数据源配置文件是 TestDB 但我的persistence.xml的数据源是

I'm new in developing apps in JBoss so I followed their tutorials specially in making the Ticket Monster. For now, I've created an Event JPA Entity and in the run, it shows that I can save an event. But when I restart my computer, it seems the event I've saved is lost, so research about it and found some info about in-memory database. My problem is how do I tell/configure my project not to use in-memory database but to use the typical database so every time I restarted my computer the data was in the database. I would like to use PostgreSQL for my database. My current datasource profile that is set to JPA is TestDB but the datasource of my persistence.xml is

<persistence version="2.1"
   xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="
        http://xmlns.jcp.org/xml/ns/persistence
        http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
   <persistence-unit name="primary">
      <!-- If you are running in a production environment, add a managed 
         data source, this example data source is just for development and testing! -->
      <!-- The datasource is deployed as WEB-INF/ticket-monster-ds.xml, you
         can find it in the source at src/main/webapp/WEB-INF/ticket-monster-ds.xml -->
      <jta-data-source>java:jboss/datasources/ticket-monsterDS</jta-data-source>
      <properties>
         <!-- Properties for Hibernate -->
         <property name="hibernate.hbm2ddl.auto" value="create-drop" />
         <property name="hibernate.show_sql" value="false" />
      </properties>
   </persistence-unit>
</persistence>

它说< jta-data-source> java：jboss / datasources / ticket-monsterDS< / jta-data-source> 而不是 TestDB 。此外，我不想使用 create-drop ，而是可以判断数据库中是否存在某些内容但不删除但使用它的值，或者如果不是现有。

it said that <jta-data-source>java:jboss/datasources/ticket-monsterDS</jta-data-source> not the TestDB. Also, I would like not use the create-drop but instead a value that could tell if there is something in the database do not drop it but use it and or create if no existing.

更新

以下我的票 - monster-ds.xml

Heres my ticket-monster-ds.xml

<datasources xmlns="http://www.jboss.org/ironjacamar/schema"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.jboss.org/ironjacamar/schema http://docs.jboss.org/ironjacamar/schema/datasources_1_0.xsd">
    <!-- The datasource is bound into JNDI at this location. We reference 
        this in META-INF/persistence.xml -->
    <datasource jndi-name="java:jboss/datasources/ticket-monsterDS"
        pool-name="ticket-monster" enabled="true"
        use-java-context="true">
        <connection-url>jdbc:h2:mem:ticket-monster;DB_CLOSE_ON_EXIT=FALSE;DB_CLOSE_DELAY=-1</connection-url>
        <driver>h2</driver>
        <security>
            <user-name>sa</user-name>
            <password>sa</password>
        </security>
    </datasource>
</datasources>

推荐答案

您可以继续使用示例中的H2数据库。 H2可以配置为写入文件。您只需要更改连接字符串。

You can continue to use the H2 database from the example. H2 can be configured to write to a file. You just need to change your connect string.

例如。 < connection-url> jdbc：h2：〜/ test;< connection-url>

查看 H2文档了解更多选项。

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