单选题 EMPDET is an external table containing the columns EMPNO and ENAME. Which command would work in relation to the EMPDET table?()
A
B
C
D
单选题 Evaluate the following statement: Which statement is true regarding the evaluation of rows returned by the subquery in the INSERT statement?()
They are evaluated by all the three WHEN clauses regardless of the results of the evaluation of any other WHEN clause.
They are evaluated by the first WHEN clause. If the condition is true, then the row would be evaluated by the subsequent WHEN clauses.
They are evaluated by the first WHEN clause. If the condition is false, then the row would be evaluated by the subsequent WHEN clauses.
The INSERT statement would give an error because the ELSE clause is not present for support in case none of the WHEN clauses are true.
单选题 Evaluate the following SQL statements that are issued in the given order: What would be the status of the foreign key EMP_MGR_FK?()
It would be automatically enabled and deferred.
It would be automatically enabled and immediate.
It would remain disabled and has to be enabled manually using the ALTER TABLE command.
It would remain disabled and can be enabled only by dropping the foreign key constraint and re-creating it.
单选题 The details of the order ID, order date, order total, and customer ID are obtained from the ORDERS table. If the order value is more than 30000, the details have to be added to the LARGEjDRDERS table. The order ID, order date, and order total should be added to the ORDERJHISTORY table, and order ID and customer ID should be added to the CUSTJHISTORY table. Which multitable INSERT statement would you use? ()
Pivoting INSERT
Unconditional INSERT
Conditional ALL INSERT
Conditional FIRST INSERT
在任何情况下,伸缩调节器处轨距的要求为()。
人类有两套影响学习的记忆系统:陈述性记忆和程序记忆。陈述性记忆是对事实或者词汇之类基本认识的记忆。而程序记忆,就是一个人“不劳而获”的记忆。程序记忆是人养成习惯和习得技巧的方式,比如骑自行车。在很多时候,这种学习是无意识的。人们用早期发育的程序记忆系统来学习复杂的东西,比如语法规则。帮助人们学习词汇的陈述性记忆系统,则需要更多时问完成发育。儿童拥有程序记忆系统,并且不受陈述性记忆系统的干扰。由此可以推出()。
宋末元初四大家
公平目标的实现可以通过()实现。
荟萃分析
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