relational algebra

常见例句

The lookup is an example of the Rails 3 relational algebra.
查询是 Rails 3 关系代数的一个示例。
is also a great introduction to this topic and shows the motivation and theory behind the "relational algebra" in ActiveRecord 3.
也是一个关于此话题的很好的介绍，解释了ActiveRecord 3 中的“关系代数”背后的的动机和理论。
This theoretical model allows, for example, that relational algebra operations to be replaced by more efficient equivalent operations whereas not interfere with the result.
例如，这种理论模型允许用更有效的等价操作来代替关系代数操作同时不影响结果。