A useful scenario is to use a UNION ALL view to model a merger, where each branch of the UNION ALL operation represents data from a branch or division of a company.
What is important is the existence of a SAN, the division of the data within the SAN and the fact that the data in the SAN is replicated to a SAN in the disaster center.
这里的重要方面包括：SAN 的存在、SAN 内数据的划分以及 SAN 中的数据复制到灾难数据中心这一事实。
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Forbes combed through data gathered annually by the Bureau of Labor Statistics, a division of the Labor Department, to find the 15 most surprising six-figure jobs.