信贷额度关系credit-in(C_ name，Limit，Credit_ balance)中的三个属性分别表示用户姓名、信贷额度和到目前为止的花费。表13-1为关系credit-in的一个具体实例。若要查询每个用户还能花费多少，相应的SQL语句应为：Select(31)From credit-in。 

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XP is (71) of interesting twists that encourage one to think--for example, how about "Test and then code"? I've worked with software companies and a few IT organizations in (72) programmer performance was measured on lines of code delivered and testing was measured on defects found-- (73) side was motivated to reduce the number of defects prior to testing. XP uses two types of testing: unit and functional. (74) , the practice for unit testing involves developing the test for the feature prior to writing the code and further states that the tests should be automated. Once the code is written, it is immediately (75) to the test suite bringing instant feedback.

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MPEG-4是(53)，MPEG-4主要由音频编码、视频编码、数据平面、(54)、缓冲区管理和实时识别等部分构成，其中数据平面包括(55)两部分。

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