【判断题】
连接运算是将两个或两个以上的关系通过一定的条件连接起来组成一个新的关系,即在关系R和关系S中选择满足-定条件的元组
A. 对
B. 错
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A
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【判断题】
Visual FoxPro 是一个关系型数据库管理系统,是一个大型数据库开发平台,是在dBASE的基础上逐步发展起来的,它有很强的数据管理功能和灵活的程序设计功能
A. 对
B. 错
【判断题】
Access 2010数据库是匈实模型 数据库系统的使用工具
A. 对
B. 错
【判断题】
在一个关系的二维表中可以唯一地标识一个元组的属性或属性组都可以作为候选键
A. 对
B. 错
【填空题】
1.在数据管理应用需求的推动下,在计算机硬件、软件发展的基础上,数据管理技术经历了___、___、___3个阶段。
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2.数据库三级模式体系结构的划分,有利于保持数据库的___。
【填空题】
3.用Access 2010创建的数据库文件,其扩展名是___。
【填空题】
4.分布式数据库是___上分散在计算机网络各结点上, 而___上属于同一个系统的数据集合。
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5.数据库是长期在计算机内的、有组织的、可共享的数据的集合。数据库能为各种用户共享,具有较小的冗余度,数据间联系紧密,并且具有较高的___。
【填空题】
6.如果两个实体之间具有m:n联系,则将它们转换为关系模型的结果是___个表。
【填空题】
7. 在关系数据模型中,把数据看成一个二维表,每一个维表称为一个___
【填空题】
8.在关系模型中用来唯一标识元组的属性组称为___
【填空题】
9.在关系数据库中,从关系中找出满足给定条件的元组,该操作可称为___。
【填空题】
万用表有()、()两种类型。
【填空题】
指针式万用表电阻档若无法调至零位,说明(),应更换新电池,否则影响()。
【填空题】
用万用表测量电流时,应让万用表与负载相( ),测量电压时,应让万用表与负载相( )。
【填空题】
测量三相异步电机绕组阻值常使用( ),测量三相异步电机绝缘应使用( )
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用数字式万用表量程小于所测参数值时,万用表将显示( )。测量直流电压时,当万用表红表笔与电源负极相接,黑表笔与电源正极相接,万用表显示( )
【填空题】
兆欧表在测量前,指针可以停留在标尺的( )位置,兆欧表在开路时,摇动手柄到额定转速,这时表针应指在( “” ) 位置。
【填空题】
用来测量交流电流的钳形电流表是由()和(  )组成的。
【填空题】
直流电的文字符号是( ),图形符号是( )。
【填空题】
交流电的文字符号是( ),图形符号是( )。
【填空题】
中性线()的文字符号是( )、接地的图形符号是( )。
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插头插座的图形符号是( 或 ), 原电池或蓄电池的图形符号是( )
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电气工程图由( )、( )、 安装接线图 三种图纸构成。
【填空题】
电气原理图由( )和( )组成。
【填空题】
国家标准规定,原理图中各元器件触点,均按( )和 ( )的自然状态下画出。
【填空题】
电气原理图中,组合开关、主令控制器、万能转换开关按手柄处于( )的状态画出, 保护开关处于( )状态画出。
【填空题】
电气安全包括()安全和( )安全。
【填空题】
保证电气安全主要有( )措施和( )措施两种。
【填空题】
工厂低压电工在每次操作前都必须用()或()对电线、电器进行验电。
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国家标准规定的安全电压等级是6V 、12V、()、()和42V。
【填空题】
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【填空题】
电流对人体的伤害形式主要有( )和()
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电流对人体的致命电流为()、安全电流为()
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人体的触电形式主要有()、()和跨步电压触电。
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设备不停电的安全距离,10KV是()米,35KV是()米。
【填空题】
高压设备发生接地故障时,室内不得接近故障点()米以内,室外不得接近故障点()米以内。
【填空题】
凡离地面()以上的地点进行工作时,都视为高空作业,应使用()。
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接地种类分为()接地,()接地和重复接地。
【填空题】
工作接地的作用是()和()。
推荐试题
【多选题】
Which three actions can be taken as a result of executing the vSphere Update Manager 6.x scan and remediation wizards? (Choose three.)___
A. Install and upgrade software in virtual machines.
B. Upgrade the firmware on ESXi host devices.
C. Upgrade and Patch ESXi hosts.
D. Install and update third-party software on hosts.
E. Upgrade virtual machine hardware.
【多选题】
Which two statements are true about deploying and using vSphere Replication? (Choose two.)___
A. ESXi hosts managed by a single vCenter Server instance require a connection between the two vSphere Replication appliances.
B. Sites managed by different vCenter Server instances require a connection between the two vSphere Replication appliances.
C. Sites managed by different vCenter Server instances require the use of Site Recovery Manager and a connection between the two vSphere Replication appliances.
D. ESXi hosts managed by a single vCenter Server instance require a single vSphere Replication appliance.
【多选题】
An administrator is attempting to power on a virtual machine, but the task is hanging at 95%. What three scenarios best explain why this problem is happening? (Choose three.)___
A. A virtual machine question is currently being posed to the administrator.
B. Another task for the virtual machine or other component is already in progress.
C. The VMware High Availability cluster has insufficient resources to guarantee failover.
D. The host has lost access to the storage device containing the virtual machine files.
E. The host is under resource contention and unable to power on the virtual machine.
【多选题】
Which three features are not supported when using Fault Tolerance in vSphere 6.x? (Choose three.)___
A. Virtual Volumes (VVOLS)
B. Storage vMotion
C. Virtual Machine Component Protection
D. vMotion
E. vSphere Distributed Switches
【多选题】
Which two storage controller configurations can be used with Virtual SAN? (Choose two.)___
A. SAS controllers in Passthrough mode
B. SAS controllers in RAID0 mode
C. SAS controllers in RAID1 mode
D. SAS controllers in RAID10 mode
【多选题】
Which three are requirements when using vMotion to move a virtual machine across vCenter Server systems? (Choose three.)___
A. Both vCenter Servers must be using Enhanced Linked Mode.
B. Both vCenter Servers must be in the same Single Sign-On Domain.
C. Time must be synchronized.
D. Duplicate VM MAC addresses must be configured.
E. Both vCenter Servers must have High Availability enabled on source and destination clusters.
【多选题】
Which two components can be used when configuring Enhanced Linked Mode? (Choose two.)___
A. vCenter Server Appliance
B. vRealize Operations Manager
C. vSphere Management Appliance
D. vCenter Server for Windows
【多选题】
An organization has a number of virtual machines that would benefit from Fault Tolerance. These include: <A single vCPU Apache Server> < A dual vCPU vCenter Server> < A quad vCPU SQL Server> <An eight vCPU Hadoop Server>. Which two virtual machines can be configured to use VMware Fault Tolerance? (Choose two.)___
A. Apache Server
B. vCenter Server
C. SQL Server
D. Hadoop Server
【多选题】
Which two badges are major badges in vRealize Operations? (Choose two.)___
A. Risk
B. Efficency
C. Workload
D. Faults
【多选题】
An administrator is deploying multiple Windows 2003 Virtual Machines from the same template. What two steps should be taken to avoid network conflicts? (Choose two.)___
A. Customize the guest operating system.
B. Install VMware Tools into the new virtual machines.
C. Copy the Microsoft Sysprep tools onto the vCenter Server system.
D. Ensure the e1000 vmnic is selected for each new virtual machine.
【多选题】
Which three conditions would prevent Storage I/O Control from being enabled on a group of datastores? (Choose three.)___
A. The datastores planned for the solution are used by different vSphere clusters.
B. A datastore planned for the solution is configured as a Raw Device Mapping file.
C. A datastore planned for the solution has three extents.
D. A datastore planned for the solution is configured as NFS.
E. The organization has an Enterprise license.
【多选题】
Which two actions are prerequisites to adding ESXi 6.x hosts to a vSphere Distributed Switch? (Choose two.)___
A. Verify that there is at least one Distributed Port Group on the Distributed Switch.
B. Verify that the Distributed Port Group have active uplinks configured in its teaming and failover policy.
C. Verify that the
D. istributed Switch has been configured with a Network Profile.
【多选题】
An organization has configured Distributed Power Management (DPM) on a vSphere 6 cluster. The organization wants to be alerted when an ESXi host has been powered down by DPM. Which two options represent the type and name of the alarm that would accomplish this? (Choose two.)___
A. DrsEnteringStandbyModeEvent
B. DrsEnteredStandbyModeEvent
C. Event-based
D. Condition-based
【多选题】
Which two allow for the disabling of Network Rollback operations? (Choose two.)___
A. Modifying the vpxd advanded configuration options and adding the config.vpxd.network.rollback key
B. Modifying the C:\ProgramData\VMware\CIS\cfg\vmware-vpx\vpxd.cfg file and adjusting the<rollback> xml tag
C. Modifying the C:\ProgramData\VMware\CIS\cfg\vmware-vpx\vpxd.cfg file and adjusting the <networkrollback> xml tag
D. Modifying the C:\ProgramData\VMware\CIS\cfg\vmware-vpx\firstboot\vpxd-service- spec.prop file and adjusting the <rollback> xml tag
【多选题】
An administrator is tasked with performing a vMotion migration of a virtual machine. The virtual machine is configured as follows: <vSphere Flash Read Cache (vFRC) enabled> <Is part of a Distributed Resource Cluster (DRS) Cluster> Which two statements are true? (Choose two.)___
A. Each ESXi host in the cluster supports multiple virtual flash resources.
B. Each ESXi host in the cluster supports one virtual flash resource.
C. DRS treats powered-on virtual machines with Flash Read Cache as having a preferred affinity to their current host and moves them only for mandatory reasons.
D. DRS treats powered-on virtual machines with Flash Read Cache as having a required affinity to their current host and does not move them.
【多选题】
An administrator is using the Host Failures to Tolerate Admission Control Policy for a vSphere High Availability ___ cluster. When configuring this setting on the cluster, the administrator sees this error message: <Insufficient resources to satisfy HA failover level on cluster > What are two likely causes for the error? (Choose two.)(AB)
A. The hosts in the cluster are disconnected.
B. A host in the cluster is displaying an HA error.
C.
D. istributed Resource Scheduler has not been configured on the cluster.
【多选题】
What are two ways to identify TCP/IP stack information? (Choose two.)___
A. Using the vSphere Web Client
B. Using esxcli network ip netstack
C. Using esxcfg-netstack
D. Using the vSphere Client
【多选题】
Which two actions are required when enabling vFlash Read Cache for a virtual machine's virtual disk? (Choose two.)___
A. A value in the Virtual Flash Read Cache text box must be entered.
B. A Flash Resource Pool for Cache size reservation must be entered.
C. The Device backing and the block size must be configured.
D. The
E. nable virtual flash host swap cache check box must be selected.
【多选题】
What two IT infrastructure components are virtualized by vSphere Essentials? (Choose two.)___
A. Networks
B. Applications
C. Storage
D. Management
【多选题】
When attempting to access a virtual machine, an administrator is unable to login using the vSphere credentials. What two options are probable causes of the authentication failure? (Choose two.)___
A. The vSphere credentials have not been granted permissions.
B. The vSphere credentials are granted read-only permissions.
C. The vSphere credentials are granted no-access permissions.
D. The vSphere credentials are not a member of the local administrator group.
【多选题】
An administrator is performing a scripted installation of ESXi 6.x. In which three locations does the script need to be? (Choose three.)___
A. PXE Server
B. HTTPS
C. FTP
D. NFS
E. VVOLs Datastore
【多选题】
In order for a company to meet regulatory requirements, all ESXi 6.x Hosts must be configured to direct logs to a syslog server. What are two ways ESXi hosts can configured for this action? (Choose two)___
A. Use the esxcli system syslog command.
B. Edit them in the ESXi host Advanced System Settings.
C. From the Syslog collector user interface of the Web Client.
D. Syslog logging is not available for
E. SXi Hosts.
【多选题】
Which three actions can be executed when an alarm is triggered? (Choose three.)___
A. Send an email.
B. Send an SNMP trap.
C. Run a script or command.
D. Run an Orchestrator workflow.
E. Send a trigger to syslog.
【多选题】
An administrator is attempting to power on a virtual machine, but is unable to do so. Which two reasons are probable causes of the failure? (Choose two.)___
A. Storage access to the virtual machine swap file has been lost.
B. One of the virtual machine VMDK files is locked.
C. Virtual machine is running CentOS 7.0 64-bit.
D. Virtual machine has Hyper-Threading enabled.
【多选题】
An administrator has configured a host profile so that ESXi 6.x hosts will point to the corporate NTP server for time synchronization. The NTP server is located at 10.0.30.213, but time has not been synchronized properly across the ESXi hosts. The administrator reviews Host Profile settings as shown in the Exhibit. Which two steps are required to resolve the issue? (Choose two.)___
A. Correct the NTP server IP address.
B. Check the host for host profile compliance.
C. Remediate the host based on the updated host profile.
D. Change the NTP server to the FQDN as IP Addresses are not supported.
【多选题】
An administrator is attempting to migrate a large Hadoop virtual machine using vMotion. The administrator notices a delay when the machine is quiesced. The Hadoop virtual machine is processing many transactions a second to an in-memory database. Which two actions would help reduce the amount of time needed to perform a vMotion on this virtual machine? (Choose two.)___
A. Use multiple NICs for the vMotion vmkernel port.
B. Use a 10Gbps Network card for the vMotion vmkernel port.
C. Add an additional management network to help transmit the data quicker.
D. Disable Fault Tolerance before performing the vMotion.
【多选题】
An administrator is installing a new network card in an ESXi 6.x host that is part of a vSphere cluster. When the host is placed into maintenance mode, the vSphere Web Client displays the progress bar at 2% for over 30 minutes. Which two are likely reasons for this occurrence? (Choose two.)___
A. Maintenance mode is unable to migrate all virtual machines from the host.
B. There is a large number of virtual machines that must be migrated from the host.
C. VMware High Availability is in the process of reconfiguring the cluster.
D. Each virtual machine on the
E. SXi host must be reconfigured to recognize the new adapter.
【多选题】
Which two events happen when Distributed Resource Scheduler (DRS) is disabled? (Choose two.)___
A. The cluster's resource pool heirarchy and affinity rules are re-established when DRS is turned back on.
B. The cluster's resource pool hierarchy and affinity rules are not re-established when DRS is turned back on.
C. The cluster's resource pools are removed from the cluster.
D. The cluster's resource pools are removed from the cluster and assigned to the hosts.
【多选题】
Which two networking connection types can be configured on a virtual switch? (Choose two.)___
A. Virtual machine portgroups
B. VMkernel services (such as NFS, iSCSI, or vMotion) to the physical network
C. Web services over the Management Network
D. NFS and FCoE storage services
【多选题】
An administrator creates a DRS cluster of eight ESXi 6.x hosts. There are 10 virtual machines balanced across the hosts. An attempt to place the first host into maintenance mode fails. What are two reasons that the host failed to enter maintenance mode? (Choose two.)___
A. The DRS cluster Automation Level is set to Partially Automated mode.
B. One of the virtual machines on the ESXi Host entering maintenance mode is configured with a DRS Host affinity rule Should run on hosts in group.
C. One of the virtual machines on the ESXi Host entering maintenance mode is configured with a DRS Host affinity rule Must run on hosts in group.
D. One of the virtual machines on the
E. SXi Host entering maintenance mode is configured with an individual Automation Level set to Partially Automated.
【多选题】
When modifying a vApp, which two vSphere entities can be added? (Choose two.)___
A. A resource pool
B. A network pool
C. A vApp
D. A folder
【多选题】
From which two locations in the inventory hierarchy can you deploy a virtual machine using a template? (Choose two.)___
A. Directly from the template.
B. From a compute resource.
C. From an existing virtual machine.
D. From a Datastore.
【多选题】
A company has decided to implement Virtual SAN within their vSphere 6.x environment. The Virtual SAN cluster will be composed of three ESXi 6.x hosts that are on the Virtual SAN Ready Node list. Each ESXi host includes: <Two SAS Controllers that support Passthrough Mode> < Four Solid State Drives (SSDs) 1TB in size each> <20 SAS Magnetic Disks (MDs) 1TB in size each> <The SSDs and MDs are evenly split between the two SAS controllers>. The company will pilot a Virtual SAN cluster utilizing VMware best practices while maximizing storage capacity. The Virtual SAN cluster will use Manual Mode. Which two Disk Group configurations would meet the stated configuration requirements? (Choose two.)___
A. 4 disk groups with 1 SSD and 5 MDs each
B. 2 disk groups with 1 SSD and 7 MDs each
C. 2 disk groups with 2 SSDs and 7 MDs each
D. 2 disk groups with 1 SSD and 10 MDs each
【多选题】
A physical Windows 2008 R2 Server is converted to a virtual machine using VMware vCenter Converter. Upon completion of the conversion and subsequent power on operation, the virtual machine fails to boot and the message below is observed in the Console of the virtual machine: <STOP 0x0000007B INACCESSIBLE_BOOT_DEVICE>. Which two potential issues may be causing this boot failure? (Choose two.)___
A. An incorrect SCSI controller was selected during conversion.
B. Incompatible software drivers were migrated into the virtual machine from the source machine.
C. The vmdk file backing the virtual machine was thick provisioned.
D. A snapshot was taken immediately after the conversion completed.
【多选题】
An administrator is configuring the Failover Order option on a vSphere Distributed Switch. Which two options should be used with IP-hash load balancing? (Choose two.)___
A. Active Uplinks
B. Standby Uplinks
C. Unused Uplinks
D. Override Failover Order
【多选题】
An administrator is configuring the Maximum Transmission Unit value on a vSphere Distributed Switch. Which two options are typical values for ESXi networking? (Choose two.)___
A. 1492
B. 1500
C. 9000
D. 9089
【多选题】
Which two configurable options apply to both virtual machine CPU and memory allocation? (Choose two.)___
A. Reservation
B. Shares
C. Resource Pool
D. Reserve All
【多选题】
When attempting to power on a Virtual Machine you observe the following error: <Cannot open the disk '/vmfs/volumes/volume/vm/vm-000002.vmdk' or one of the snapshot disks it depends on.> Which three actions will be the best solutions to address this problem? (Choose three.)___
A. Verify that the virtual machine's disk files are present.
B. Investigate the host and virtual machine log files.
C. Verify the vmdk descriptor files and if required, recreate them.
D. Delete the disk file preventing the power on operation.
E. Migrate or register the virtual machine to a different host.
【多选题】
An administrator has been tasked with enabling High Availability ___ on a cluster in a vSphere 6.x environment with default settings. The cluster configures properly and there are no errors. The next day when powering on a virtual machine, an error is presented: <Not Enough Failover Resources>. Which three scenarios are likely causes of this error message? (Choose three.)(CDE)
A. The default VM Monitoring Sensitivity is set too high.
B. There are not enough datastore heartbeat datastores configured by default.
C. The default slot size in the cluster is set too high.
D. There are virtual machines with large CPU reservations.
E. A host is in maintenance mode for a replacement of a failed Hard Drive.
【多选题】
vMotion can be performed between which three physical boundaries? (Choose three.)___
A. Between two vCenter Server Systems
B. Between two vSphere Distributed Virtual Switches
C. Between two vCenter Server Datacenter objects
D. Between two VMware NSX Layer 4 segments
E. Between two NFS datastores