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有关系模式：系(系号，系名，系办公电话)，教师(教师号，教师名，职称，聘任日期，工资，所在系号)。现要定义下列约束： Ⅰ．系号是系关系的主码，教师号是教师关系的主码 Ⅱ．职称列的取值只能为“教授”、“副教授”、“讲师”、“助教”和“其他” Ⅲ．教授的默认工资为10000元，副教授的默认工资为8000元，讲师的默认工资为5000元 Ⅳ．每个教师的所在系号不能为空，且其值必须在系关系中存在若在数据库中实现以上约束，需要使用触发器才能实现的是______。
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在SQL Server 2000中，设有教师表(教师号，姓名，所在部门，工资)。现需统计指定部门的工资总和，有下列标量函数： Ⅰ．CREATE FUNCTION f_SumSalary( @bm varchar(30)) RETURNS int BEGIN RETURN (SELECT SUM(工资) FROM 教师表 WHERE 所在部门=@bm) END Ⅱ．CREATE FUNCTION f_SumSalary( @bm varcbar(30)) RETURNS int BEGIN RETURN (SELECT COUNT(工资) FROM 教师表 WHERE 所在部门=@bm) END Ⅲ．CREATE FUNCTION f_SumSalary( @bm varchar(30)) RETURNS int BEGIN DECLARE @X INT SET @X=(SELECT SUM(工资) FROM 教师表 WHERE 所在部门=@bm) RETURN @X END Ⅳ．CREATE FUNCTION f_SumSalary( @bm varchar(30)) RETURNS int BEGIN DECLARE @X INT SELECT @X=SUM(工资) FROM 教师表 WHERE 所在部门=@bm RETURN @X END 上述函数中能正确实现该功能的是______。
I won"t be modest. I am gratified to discover that a paper I penned on inequality made its way into Matt Miller"s Washington Post column last week. Mr Miller asks why rising inequality has not【C1】______America"s least-favored classes to agitate for a【C2】______He agrees with my verdict: that access to【C3】______goods among the least well-off has ensured that material inequality is not as【C4】______as income inequality. 【C5】______modem conveniences have taken some of the【C6】______out of a relatively small income. This in turn has【C7】______the drive to seek causes of and cures for【C8】______"s discomfort. So the gap between rich and poor is sometimes less【C9】______, even if it is great and growing. Day-to-day experience is mostly a matter of our【C10】______circumstances, and if those are【C11】______enough, a widening gap in income, consumption or wealth is【C12】______to come often to our attention. Even if the abstract fact of rising inequality does come across our radar, it may【C13】______our sense of justice only if we"ve become convinced that inequality itself is【C14】______, or if we face related catastrophes. When I wrote the paper, official measures of income inequality had increased a good deal over the past few decades【C15】______consumption inequality seemed to have remained【C16】______New research suggests that consumption inequality has been increasing with income inequality【C17】______This may be true, but it seems【C18】______to the question of why America"s poor aren"t storming the barriers. The consumption data concerns how much we【C19】______, not how we experience what we buy, and that"s the real issue. Even if we could agree that inequality in real standards of living is rising, this is not something we actually experience unless we are hungry, or【C20】______with the entertainments of our leisure. 【C6】
SQL Server 2000支持的用户自定义函数包括______。
创建存储过程的SQL语句正确的是______。
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