The InnoDB engine has a feature known as clustered indexes. Which three statements are true about clustered indexes as used in InnoDB?（）
A . A primary key must exist for creation of a clustered index
B . A clustered index allows fulltext searching within InnoDB
C . The first unique index is always used as a clustered index and not a primary key
D . A clustered index provides direct access to a page containing row data
E . If no indexes exist, a hidden clustered index is generated based on row IDs
F . A primary key is used as a clustered index
G . A clustered index is a grouping of indexes from different tables into a global index for faster searching
相似题目
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A common rail engine has only one or two high pressure pumps in operation at the same（）time, and the injection into each cylinder.
A . can’t be controlled very precisely
B . can’t be controlled as flexibly as the separate pump system
C . can be controlled as flexibly as the separate pump system
D . can be controlled more precisely and flexibly
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A turbocharged, four-stroke/cycle diesel engine has a larger valve overlap than a naturally aspirated four-stroke/cycle diesel engine, in order to in crease the （）.
A . temperature of the exhaust gases
B . energy supplied to the turbocharger
C . air pressure to the intake manifold
D . purge of exhausted gases from the cylinder
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Which of the following adjustments is always required whenever the diesel engine governor oil has been drained and renewed?（）
A . speed droop
B . compensation
C . idle speed setting
D . load limit control
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If a diesel engine has been stopped because of piston seizure due to severe overheating, the crankcase（）
A . inspection covers should not be opened until the engine has cooled
B . ventilation system should be continued in operation for one hour for cooling
C . scavenge pump should be immediately secured to prevent loss of lube oil
D . explosion covers should be opened slightly to provide extra ventilatio
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Before starting a diesel engine that has an engine driven lube oil pump, the engineer should （）.
A . open the bypass line
B . cut in the lube oil cooler
C . pressurize the lube oil system
D . top off the expansion tank
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The cooling water of the diesel engine should be treated, because it has（）
A . alkale scence
B . acidity
C . salinity
D . impurity
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0ur engine has a（）of 10000 horse-power.
A . liability
B . ability
C . capacity
D . responsibility
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If a hydraulic governor has been refilled with oil, the engine should be operated until it reaches normal temperaturethen the air should be purged, and the（）
A . rack position should be adjusted
B . compensating needle valve should be opened fully compensating
C . needle valve should be adjusted to stabilize operation
D . speed limiting device should be adjusted
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Fuel has to be injected into the engine at a high pressure so that it （） correctly.
A . is purified
B . in timed
C . is compressed
D . atomize
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Your vessel has a midship engine room and the cargo is concentrated in the end holds.The vessel is（）.
A . sagging with tensile stress on main deck
B . sagging with compressive stress on main deck
C . hogging with tensile stress on main deck
D . hogging with compressive stress on main deck
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A lube oil sample taken from the main engine lube oil system has dark yellow opaque color.This is the result of （）
A . water contamination
B . mixing oils of two widely different viscosities
C . overheating
D . aeratio
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Why should you wear a self-contained breathing apparatus before entering the engine room after the fixed CO2 system has been discharged to combat a major fire?（）
A . Because carbon dioxide dilutes the oxygen concentration in the atmosphere and may cause asphyxiation
B . Because carbon dioxide breaks down in a fire into carbon monoxide which may cause blood poisoning in the person breathing this gas
C . Because carbon dioxide is a colorless and odorless gas that becomes highly toxic in the presence of high temperatures and will quickly incapacitate a person exposed to this gas
D . This action is unnecessary as carbon dioxide is not poisonous nor toxic but is a relatively harmless ga
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When reentering an engine room that has been flooded with CO2, the investigating team should initially（）.
A . leave the access door partially open
B . enter from the lowest level
C . enter from the highest level
D . attempt to operate machinery
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In heavy marine engine the practice is to drive the engine on（）which has previously been stored in starting air reservoirs.
A . electric motor
B . hydraulic motor
C . compressed air
D . turning gear
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A four-stroke cycle, turbocharged, 1000 horsepower diesel engine has been operating under loadThe load suddenly increases, causing excessive black exhaust smoke, and a rapid rise in the lube oil temperatureIn response to this condition, you should:（）
A . reduce load
B . check your exhaust
C . adjust cooling water temperature
D . increase lube oil flow
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If a cam-controlled engine has a normal injection pressure at rated speed,the injection pressure will be（）at slow speed.
A . a little lower
B . a little higher
C . too low
D . exactly the same
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A diesel engine is similar to a gasoline engine except that the former has no （）.
A . cross-head
B . cylinder
C . connecting rod
D . spark plug
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The engine has one or two group of fuel pumps, depending upon （）.
A . the number of fuel valves
B . the number of cylinders
C . the speed of engine
D . the power of engine
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In heavy marine engine the practice is to drive the engine on____ which has previously been stored in starting air reservoirs.
A.electric motor
B.hydraulic motor
C.compressed air
D.turning gear
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The technology has several advantages earlier attempts to engineer meat in vitro .
A、in comparison of
B、in comparison to
C、compare with
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has the best engine design in terms of saying money？_________
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Starting air is shut off from the engine as soon as sufficient speed has been reached.（)
是
否
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The old man has three sons.（) is a doctor,（) is a teacher,（)is an engineer.
A、 One / one / nother
B、 Another/ another / the other
C、 One/ another/ the other
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Which of the following sentence has the meaning with &8220;Take off aborted due starboard engine EGT abnormal.&8221;（）
A．Take off was can celled due to number one engine inoperative
B．Take off was stopped due to tail engine problem
C．Take off was abandoned due to the right engine exhausted temperature too high
D．Take off was aborted due to the left engine pressure too low
