第1题：
Consider the query:Mysql＞ SET @run = 15;Mysql＞ EXPLAIN SELECT objective, stage, COUNT (stage)FROM iteminformationWHERE run=@run AND objective=’7.1’GROUP BY objective,stageORDER BY stage;The iteminformation table has the following indexes;Mysql＞ SHOW INDEXES FROM iteminformation:This query is run several times in an application with different values in the WHERE clause in a growing data set.What is the primary improvement that can be made for this scenario?（）
A.Do not pass a user variable in the WHERE clause because it limits the ability of the optimizer to use indexes
B.Add an index on the objective column so that is can be used in both the WHERE and GROUP BY operations
C.Drop the run_2 index because it has caused a conflict in the choice of key for this query
D.Execute the run_2 index because it has caused a conflict in the choice of key for this query
E.Add a composite index on (run,objective,stage) to allow the query to fully utilize an index
第2题：
The systems of universities are very vulnerable because they are decentralized and accessible to many people.
第3题：
The students become very__________ to Minneapolis because they can buy a house after working there for several years.
A． attracted
B． attribute
C． attempted
D． attended
第4题：
第5题：
第6题：
Computer systems consist of two very different types of elements: Hardware, which includes all the physical things that can be touched and(71)which tells the hardware how to do.
A．Operating system
B．I/O devices
C．Courseware
D．Software
第7题：
______ play a very important part in hydraulic systems by preventing interaction between different parts of the hydraulic circuit.
A.Motors
B.Check valves
C.Safety valves
D.Reducing valves
第8题：
A、in common
B、share
C、same
D、different
第9题：
第10题：