Allen began the series after a post where he gives what his experience has shown as the three rules for development with relational databases. The rules are.

Allen在发布了关系型数据库开发的三个原则的经验总结文章之后，就开始写后续的系列文章了。

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"Downton Abbey" centers on a British aristocrat, Robert Crawley, the Earl of Grantham, who has three daughters but no sons to whom he can leave his estate, as required under British property rules at the time.

WSJ: Money Lessons From 'Downton Abbey'