Red Hat Summit 红帽全球峰会支持控制台（Console）开发人员开始试用联系人

此内容没有您所选择的语言版本。

9.9. VDB Reuse

VDBs may reuse other VDBs deployed in the same server instance by using an "import-vdb" declaration in the vdb.xml file (see Section 9.1, “VDB Definition”). An imported VDB can have its tables and procedures referenced by views and procedures in the importing VDB as if they are part of the VDB. Imported VDBs are required to exist before an importing VDB may start. If an imported VDB is undeployed, then any importing VDB will be stopped.
An imported VDB includes all of its models and may not conflict with any model, data policy, or source already defined in the importing VDB. Once a VDB is imported it is mostly operationally independent from the base VDB. Only cost related metadata may be updated for an object from an imported VDB in the scope of the importing VDB. All other updates must be made through the original VDB, but they will be visible in all imported VDBs. Even materialized views are separately maintained for an imported VDB in the scope of each importing VDB.

Example 9.3. Example reuse VDB XML

<vdb name="reuse" version="1">

    <import-vdb name="common" version="1" import-data-policies="false"/>

    <model visible="true" type="VIRTUAL" name="new-model">
         <metadata type = "DDL"><![CDATA[
              CREATE VIEW x (
                y varchar
                ) AS 
                  select * from old-model.tbl;
         ]]>
         </metadata>
    </model>
</vdb>
Copy to Clipboard Toggle word wrap
In the above example the reuse VDB will have access to all of the models defined in the common VDB and adds in the "new-model".
返回顶部
Red Hat logoGithubredditYoutubeTwitter

学习

尝试、购买和销售

社区

关于红帽文档

通过我们的产品和服务，以及可以信赖的内容，帮助红帽用户创新并实现他们的目标。 了解我们当前的更新.

让开源更具包容性

红帽致力于替换我们的代码、文档和 Web 属性中存在问题的语言。欲了解更多详情，请参阅红帽博客.

關於紅帽

我们提供强化的解决方案，使企业能够更轻松地跨平台和环境（从核心数据中心到网络边缘）工作。

Theme

© 2025 Red Hat