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How many unique area addresses can the ISIS TLV 1 carry?()
Globally Unique MME Identifier(GUMMEI)标识用来唯一标示一个MME网元。
Which two components are unique to controller-based wireless installations? ()
Which of the following virtualization options are unique to AIX and PowerVM compared to other UNIX based offerings?()
Ireland is unique among European countries for().
Which pseudocolumn could you use to identify a unique row in a Flashback Versions Query?()
What makes Silicon Valley such a unique entity? There are several crucial factors. First and foremost, it has the largest concentration of brilliant computer professionals and the best supporting services in the world, and easy access to world-class research institutions, like Stanford University, which continually nurtures would be geniuses which the industry needs in order to move forward. Without these advantages, the Valley would be a different place. Secondly, it actively encourages, or even exalts, risk-taking. Hence, failure holds no terror and there is no stigma attached to a failed effort. On the contrary, they will try even harder next time round. A third decisive factor is the vital role of venture capitalists who willingly support promising start-ups with urgently needed initial capital to get them started. Some would even give failed entrepreneurs a second chance if convinced that a flesh concept might lead to eventual success. Of equal importance, many bright young people and middle level professionals are keen to work for a new venture at substantially reduced remuneration, as it offers more scope for entrepreneurship and job satisfaction than the established companies.
一个数据表中只能有一个主键约束,但可以有多个UNIQUE约束。
下列关于CREATE UNIQUE INDEX IDX1 ON T(C1,C2)语句作用的说法,正确的是()。