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为什么程序关闭的时候报 access violation add address 错误?
SauMa
2007-01-04 11:00:30
每次程序关闭的时候就会报这个错,这是怎么回事呢
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为什么程序关闭的时候报 access violation add address 错误?
每次程序关闭的时候就会报这个错,这是怎么回事呢
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我不懂电脑
2007-01-04
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有内存被释放后,又访问了。
___NULL
2007-01-04
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这个问题不好说,估计什么东西还没关闭,就被你 Terminate 了,但设断点运行却给了足够的时间来完成那个任务
SauMa
2007-01-04
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这得给什么地方的代码啊?我关闭程序就直接调用Application->Terminate(),然后就报错,但是我再这里下断点跟进去又么有错,可以正常退出
daydayup234
2007-01-04
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给点代码才知道
SauMa
2007-01-04
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谢谢如风,我把程序改了一下,可以了
现在我想在子窗口关闭的时候发消息给主窗体,把子窗体指针delete然后再赋NULL
下面是添加的消息映射
BEGIN_MESSAGE_MAP
MESSAGE_HANDLER(WM_FORM_CLOSE,TMessage,CMMessage)
END_MESSAGE_MAP(TForm1)
自定义消息,程序一起来运行到这里END_MESSAGE_MAP(TForm1)这里就报了stack overflow,这是为什么呢
donwmufromdying
2007-01-04
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个人认为你在关闭子窗口和主窗口时的问题。一般的一个form1调用另外一个form2(动态创建的)这个流程:Form2=new TForm2(this);
Form2->ShowModal();
Form2->Close();
Form2=Null;
donwmufromdying
2007-01-04
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你最好把你程序中动态分配的内存显式释放掉,比如:free,dealloc...,Close等等,特别是一些对象的实例释放,比如:form
SauMa
2007-01-04
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我打开了一个子窗口,在子窗口运行部分代码后,关闭子窗口,在关主窗口就出错,但是关子窗口的时候没出错
jiangshx
2007-01-04
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看看运行程序时都执行了哪些操作,导致了这个错误。
比如:如果运行程序以后,直接退出就出错,那就可能是在程序启动一些事件中,某段代码有问题,可能指针越界之类的。试着屏蔽该段代码或其中部分代码,看看还出错不,以此判断代码错误的位置。
Access
violat
ion
at
add
ress
故障的解决方法 win7图文解决方案
Access
violat
ion
at
add
ress
故障的解决方法,图文说明,帮您轻松解决^_^
Visual_Studio.NET相关词汇中英翻译
abstract class 抽象类 accelerator 快捷键 accelerator mapping 快捷键映射 accelerator table 快捷键对应表
access
modifier 访问修饰符
Access
Pack 访问包
access
specifier 访问说明符
access
violat
ion
访问冲突
access
ibility 辅助功能
access
ibility domain 可访问域
Access
ibility Opt
ion
s 辅助功能选项
access
or 访问器 act
ion
操作 Active Directory hierarchy Active Directory 层次结构 active document 活动文档 Active Document Containment 活动文档包容 active end 活动结尾 active object 活动对象 active point 活动点 Active Template Library 活动模板库 ActiveX Component ActiveX 组件 ActiveX Control ActiveX 控件 ActiveX control container ActiveX 控件容器 ActiveX Control Interface Wizard ActiveX 控件接口向导 ActiveX Control Test Container ActiveX 控件测试容器 ActiveX Designer ActiveX 设计器 ActiveX Document Migrat
ion
Wizard ActiveX 文档移植向导 ActiveX-enabled 支持 ActiveX 的
Add
key/ Multiply key/ Substract key/ Devide key 加号键/ 乘号键/ 减号键/ 除号键
Add
-In 外接
程序
Add
ress
Book 通讯簿
add
ress
space 地址空间 Administrator Mode 管理员模式 advise sink 通知接收 aggregate 聚合 Airbrush 喷枪 All Tables 所有表 allocat
ion
hook 分配挂钩 Alternate text "替换文字,备用文本" Always On Top 总在最前面 ambient 环境 ambiguous 不明确 ampersand “&”符 ampersand (&) “and”符 (&) anchor 锚定 (v.);定位点 (n.) animat
ion
control 动画控件 apartment-model threading 单元模型线程 applicat
ion
framework 应用
程序
框架 Applicat
ion
Wizard 应用
程序
向导 Apply Now 立即应用 apply to similar 应用到相似项 argument 参数 Arrange Tables 排列表 array initializer 数组初始值设定项 array rank 数组秩 arrow cap 箭头帽 ARROW key 箭头键 ArrowHourGlass 箭头沙漏 ArrowQuest
ion
箭头问号 article family 文章族 assembly
程序
集;汇编 assembly manifest
程序
集清单 assert 断言 assign 分配 associate 关联 asterisk (""*"") 星号(“*”) asynchronous moniker 异步名字对象 asynchronous peek operat
ion
异步查看操作 ATL Object Wizard ATL 对象向导 atomic operat
ion
原子操作 attached table 附加表 attribute 属性 Attributed Component Wizard 属性化组件向导 Attributed Programming 属性化编程 Attributes Property Attributes 属性 Authenticat
ion
身份验证 authorable 可创作(的) Auto complet
ion
for commands 自动完成命令 Auto Increment 自动增加 Auto Syntax Check 自动语法校验 Automatic 自动 automat
ion
自动化 automat
ion
-enabled 启用自动化
Borland Delphi 2005 Architect Update 3
Borland Delphi 2005 Architect Update 3----------Report #: Short Descript
ion
: Rating: Status12241 IntToHex returns lowercase letters0.00 of 5 Closed11881 TStringStream constructor for .NET sets Posit
ion
incorrectly0.00 of 5 Closed11787
Access
violat
ion
using Code Insight when editing the uses clause0.00 of 5 Closed11759 TList instance leaked in DBCommon.pas when using IN operator in Filter express
ion
5.00 of 5 Closed11651 New EllipsisPosit
ion
property causes text to be invisible & process to hang5.00 of 5 Closed11471 Cannot manage StarTeam associat
ion
since applying Update20.00 of 5 Closed11353 (strict) protected nested class become public3.67 of 5 Closed11314 Too much inlining yields unstable compiled code.0.00 of 5 Closed11266 Inline causes compile error : F2084 Internal Error SCR765.00 of 5 Closed11193 Inlined funct
ion
affects working of the enclosing for loop0.00 of 5 Closed11184 [Fatal Error] F2084 Internal Error: ILLK26340.00 of 5 Closed11069 Compact the TApplicat
ion
.ProcessMessage code fragment for Unicode handling5.00 of 5 Closed10918 TColorBox control custom color select
ion
causes AV0.00 of 5 Closed10873 Internal error: URW 793 when using constant struct with enums2.00 of 5 Closed10861
Access
Violat
ion
when compiling code with default index property0.00 of 5 Closed10772 Designer improperly handles controls tagged with [ToolboxItem]0.00 of 5 Closed10669 TWideStrings has no GetEnumerator method0.00 of 5 Closed10661 Switching between form and source view cause long delay4.67 of 5 Closed10567 Ability to create all VCL packages0.00 of 5 Closed10498 D2005: DataSet lots of methods missing in code complet
ion
0.00 of 5 Closed10450 The Ellipse is drawn over some of the capt
ion
text when a form is docked in IDE0.00 of 5 Closed10381 Constant array of procedural types crashes compiler5.00 of 5 Closed10376 The Delphi 2k5 IDE UpTime & project loading is very SLOW4.00 of 5 Closed10314 Error Insight fails to flag an error4.00 of 5 Closed10248 Alignment Palette in VCL form designer malfunct
ion
s5.00 of 5 Closed10190 List view selected item no longer selected5.00 of 5 Closed10009 Double-click in the Search Results window0.00 of 5 Closed9912 Press Enter on Component crashes Delphi 20050.00 of 5 Closed9847 Transact
ion
al Object Wizard Missing0.00 of 5 Closed9712 The XML documentat
ion
feature doesn't associate comments with the correct symbols5.00 of 5 Closed9690 "Cannot focus a disabled or invisible window" in IDE0.00 of 5 Closed9666 Code Complet
ion
doesn't show all available items when using overload5.00 of 5 Closed9639 Active Form wizard not available in Delphi 2005 but ment
ion
ed in online help5.00 of 5 Closed9634 IDE response too SLOW4.63 of 5 Closed9578 TXPManifest + TFrame + TLabel + TRadioGroup = bad5.00 of 5 Closed9477 Delphi .NET assembly references with strong names5.00 of 5 Closed9254 Incorrect reference public key token included into Delphi8 strong-named assembly metadata4.00 of 5 Closed9021 Memory Leak in TreeView0.00 of 5 Closed8866 Assigning long string values (greater than 8192 characters) to TStringFields results in
access
violat
ion
.5.00 of 5 Closed8785 Filter or Ranges on Nested Dataset's should restrict master as well.0.00 of 5 Closed8417 TCustomSQLDataSet.GetFieldData implementat
ion
0.00 of 5 Closed8229 Error in code when database doesn't support schema/owner names5.00 of 5 Closed8032 Show modified code in the scrollbar0.00 of 5 Closed8021 TIndexDef.Assign Doesn't copy DescFiels and CaseInsFields5.00 of 5 Closed8001 SQLDataset doesn't call .Close on dbExpress driver cursor when closing5.00 of 5 Closed7912 TCustomClientdataset: properties "IndexDefs" and "IndexName" should be public0.00 of 5 Closed7872 double except
ion
in method TDataSetProvider.InternalGetRecords5.00 of 5 Closed7809 SetOpt
ion
alParam don't work0.00 of 5 Closed7768 An Easy Feature Request: TDataset.CopyFields4.00 of 5 Closed7290 Grid's funct
ion
ality enhancement5.00 of 5 Closed7199 Class Complet
ion
erroneously
add
s fields to a complete class if the getter funct
ion
s starts with F5.00 of 5 Closed7082
Add
SSE3 / PNI instruct
ion
s to the BASM5.00 of 5 Closed7005 New control request - TDBStaticText -
Add
possibility to have Edge Borders0.00 of 5 Closed6985
Add
node for unit name in Find in Files results in Message Window0.00 of 5 Closed6803 WebToolBar problem with buttons0.00 of 5 Closed6558 AV in DBGrid when destroying DataSet0.00 of 5 Closed6428 Labels disappear with XPManifest5.00 of 5 Closed6368 Resolving lookup- & calculated fields to datafields4.00 of 5 Closed6238 DBNavigator and DBGrid compliant with Federal Sect
ion
5080.00 of 5 Closed6021 Labels not visible in Windows XP0.00 of 5 Closed5951 Internal error: SY5764.44 of 5 Closed5812 TComboBox.Focused method does not always return good results.1.00 of 5 Closed5803 Unable to delete component if code editor minimized in saved desktop5.00 of 5 Closed5763 Cannot debug datamodule containing many objects0.00 of 5 Closed5699 Apache shared modules do not work with Apache 2.0.4x5.00 of 5 Closed5592 New event OnValidate that is fired before applying updates2.00 of 5 Closed5336 fatal error: Internal Error: L6812.33 of 5 Closed5283 Cannot read complete compiler error message.0.00 of 5 Closed5280 MessageDlg returns mrNone instead of mrCancel when aborted5.00 of 5 Closed5248 Assert fails to break and leaves FPU invalid op except
ion
set.4.50 of 5 Closed4627 Cannot assign -2147483648 into INTEGER Variable4.00 of 5 Closed4624 A way to set both Width and Height of TBitmap (speed reason)4.85 of 5 Closed4581 Field descript
ion
and Label3.00 of 5 Closed4444 IncMilliSeconds...IncHour with DateTime<0 wrong0.00 of 5 Closed4343 Proposal of modificat
ion
of the TDataSet.Post method in DB.pas unit1.00 of 5 Closed4184 Delphi DLL using sharemem called from VC++ exe AV on exit3.25 of 5 Closed4172 tFrames and XPMan hiding controls5.00 of 5 Closed3850 TGraphicControl descendants invisible in frames with XP Manifest4.60 of 5 Closed3792 TryEncodeDateTime not correct for dates before Dec. 30, 18995.00 of 5 Closed3776
Add
full IDL support0.00 of 5 Closed3718 Automatic Required setting of TField not consistent with SQL3.71 of 5 Closed3542 Strange limits in property CommandText2.40 of 5 Closed2881 DBGrid doesn't repaint when Enabled changed.5.00 of 5 Closed2625 Impossible to open a .TLB into the TLB Editor if missing uses reference3.50 of 5 Closed2608 Compiler crashes, dcc70.dll Read of
add
ress
000000004.00 of 5 Closed2572 Unable to sort on columns in module view3.00 of 5 Closed2382 TListView doesn't update correctly in OwnerData mode.4.00 of 5 Closed2276 'deprecated' warning appears when it shouldn't4.31 of 5 Closed2258 Failure to parse/compile integer constant --2147483648 and lower4.86 of 5 Closed2236 Delphi converts Text DFM's to binary with these steps4.71 of 5 Closed1685 Compiler error message refers to HIGH when it should be LOW3.43 of 5 Closed1455 GetRange method3.38 of 5 Closed1209 Context help does not work for TComboboxEx3.67 of 5 Closed1177 ResourceString limitat
ion
of 1024 characters3.89 of 5 Closed(出处:www.borland.com)
TICQClient Vers
ion
//// TICQClient Vers
ion
1.18f// (C) Alex Demchenko(alex@ritlabs.com)// http://www.cobans.net////-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=[ Legend: ][ +
Add
ed feature ][ * Improved/changed feature ][ - Bug fixed (I hope) ]16-September-2002, Vers
ion
1.18f (fix release)[+]
Add
ed .manifest file in Example project for better WinXP GUI compatability[-] Fixed SMS reply receiving (Thx! to Nick Anikin)[-] Fixed OnConnect
ion
Refused event, it wasn‘t called when connect
ion
with ICQ server was lost (Thx! to Mironov Serghei)[-] Applicat
ion
containing TTimer on the same form as TICQClient generated
Access
Violat
ion
error (Thx! to Simon de James)07-September-2002, Vers
ion
1.18[!] Sorry that HTTP proxy support wasn‘t
add
ed in this release, it‘s impossible due to blocking sockets architecture, but ICQ HTTP PROXY protocol has been discovered and parsed (for developers: see MySocket.pas)[!]
Add
ed file receiving see ‘File Transfers‘ in Help.chm[+]
Add
ed RequestInfoShort procedure & OnUserInfoShort event for requesting the short info about user[+]
Add
ed LastError: String property in TICQClient[+]
Add
ed ICQClientVer_Major, ICQClientVer_Minor constants in ICQWorks.pas[*] Some work-speed improvements[*] Improved info request/response procedures & events[*] Improved white pages (more compatible with ICQ2002a)[*] Improved sockets: data sending should work better now (especially with badly internet connect
ion
)[*] Improved TICQClient timeout timer[*] Contacts & contacts requests can be sent/received also through server now, see SendContacts, RequestContacts funct
ion
s[*] OnPasswordChanged events moved to OnInfoChanged event.[-] Finally fixed the bug which doesn‘t allow to close the applicat
ion
having TICQClient while Windows restarting/shutting down[-] Fixed bug: users where not
add
ed to invisible list while receiving server side lists in Example (bug in Example) (Thx! to Attila)[-] Fixed age field in OnUserFound event when searching white pages[-] Fixed disconnect
ion
bug in direct connect
ion
sess
ion
s (server doesn‘t handled disconnect
ion
events)[-] Fixed
access
violat
ion
on receiving OnInfoBackGround events with different count in Pasts & Affiliat
ion
s lists (bug in Example)[-] Fixed UTF8ToStrSmart funct
ion
, now it should convert UNICODE strings from ICQ server nearly perfectly ;) (Thx! to Alexander Vaga)[-] Fixed TMySock
access
violat
ion
when destroying the object after socket reported OnConnectError[-] Lots of
access
violat
ion
fixes, which appear while using heavily TICQClient as a non-visual object17-August-2002, Vers
ion
1.17[!]
Add
ed server side list upload support (you can even
add
users into SSL without authorizat
ion
!), see ‘Server Side Lists‘ in Help.chm[!]
Add
ed Miranda-icq database support in TICQDb component, see DbType property in Help.chm[+]
Add
ed ignore list support, see Server Side Lists in Help.chm[+]
Add
ed OnURLFound event in TICQDb[+]
Add
ed OnChangePasswordError event, called when password cannot be changed[+]
Add
ed new ERR_LOGIN type in OnError event, for more info see Help.chm file - OnError event[+]
Add
ed SetAuthorizat
ion
procedure setting ‘authorizat
ion
required‘ and ‘webaware flag‘, see SetAuthorizat
ion
procedure, OnAuthorizat
ion
ChangedOk event[+] ICQ databases can be open now while ICQ is running[*]
Add
ed authorize parameter in OnUserFound event[-] Fixed internet
add
ress
resolving, which caused connect
ion
errors on some Win98 systems[-] Received SMS messages were not converted from UTF-8 format[-] Fixed devis
ion
by zero in TICQDb component10-August-2002, Vers
ion
1.16[+]
Add
ed SMS reply event, now you can receive messages sent through cellular, see OnSMSReply event (Thx! to Olivier)[+]
Add
ed connect
ion
timeout support, see Connect
ion
Timeout property[+]
Add
ed OnError event, now you can understand why you‘ve been disconnected :)[+] Answers on info changing, see OnInfoChanged event[+] An opt
ion
disabling direct connect
ion
s, see property DisableDirectConnect
ion
s[*] Direct connect
ion
s are estabilished now through proxy (if any)[*] Removed thread layer while resolving IPs in SOCKS proxies[*] MySocket.pas improvements, fixed potential
Access
Violat
ion
bugs[*] TProxyType moved to ICQWorks.pas[-] Fixed SetSelfInfoMore procedure: languges were broken[-] Fixed message ACKs[-] Proxy packets were dumped in OnPktParse event[-] SendSMS procedure didn‘t convert Text to UTF-8 format[-] Client should disconnect now on receiving malformed packets06-August-2002, Vers
ion
1.15[!] SOCKS4, SOCKS5 proxy support, only experimental now, please test it[+]
Add
ed keep alive packets support, see procedure SendKeepAlive[+]
Add
ed OnOnlineInfo event providing advanced info about users going online: Internal & External IPs, Port, Protocol vers
ion
.[-] Messages from Mac clients were not received (Thx! to AV(T))[-] Fixed range checking errors in TICQClient component (Thx! to Klimashev I.A.)[-] Fixed unicode strings in server side contact list group names[-] Fixed icon displaying in UserSearch form of the Example project[-] Some help fixes and modificat
ion
s16-July-2002, Vers
ion
1.11[!]
Add
ed TICQDb example. See DbConverter.[+] Impoved SMS support, see OnSMSAck & OnSMSRefused events.[-] TICQDb: .idx and .dat files were not closed after importing[-] Offline messages were not received (Thx to Sergey Sokolov)15-July-2002, Vers
ion
1.1[!] Importing messages, urls, contacts(with their info) & owner‘s info (including password!) from ICQ2000x, ICQ2001x, ICQ2002a databases. See TICQDb component.[!] SMS messages are working :) (Thx! to Nick Barrett)[*] property Pasword changed to property Password (sorry for spelling)[*] New help file! (.chm format)[*] Removed
Add
ContactVisible,
Add
ContactInvisible funct
ion
s, use VisibleList.
Add
, InvisibleList.
Add
instead.[-] Fixed bug with Visible/Invisible lists: after
add
ing a user to your vis./inv. lists you was disconnected from server. (Thx! to Karloz R.)[-] Sorry that new Russian help file isn‘t included in this release, I have‘t got time for it bacause of going in the summer hollidays :)12-July-2002, Vers
ion
1.0 (Release!)[+]
Add
ed contacts request, see RequestContacts funct
ion
[+]
Add
ed acks on every direct packet, see OnDirectPacketAck event.[-] Russian help didn‘t contain some funct
ion
s & events[-] Main example should work now in Delphi5 & other compatability issues10-July-2002, Vers
ion
0.9[!] Direct connect
ion
s are supported now![!] OnMessageRecv & OnOfflineMsgRecv are divided now into OnMessageRecv/OnURLRecv & OnOfflineMsgRecv/OnOfflineURLRecv, so the MsgType param isn‘t used now[+] Sending/Receiving messages directly to client[+] Sending/Receiving contacts[+] Receiving contacts requests[+] Improved MySocket.pas, now it works safier and doesn‘t use any threads05-July-2002, Vers
ion
0.8[+]
Add
ed Russian translat
ion
of Help.html. See HelpRus.html.[+]
Add
ed password changing procedure. See ChangePassword procedure & OnChangePasswordOk event.[+]
Add
ed unregistering the existing UIN. See UnregisterUIN procedure and OnUnregisterBadPassword, OnUnregisterOk events.[-] UNICODE(UTF-8) names in the server side contact lists were not converted to ASCII.[-] Packet dumper now parses more packets on channels 1 & 405-July-2002, Vers
ion
0.7[+] Now you can register new UIN from TICQClient! See RegisterNewUIN procedure and OnNewUINRegistered, OnNewUINRefused events.[+] Auto-away messages support. See RequestAwayMsg procedure, OnAutoMsgResponse event and AutoAwayMessage property.[-] Since v0.6 ‘White Pages‘ did not work properly (Thx! to Ozan Kulahci)[-] Login event was called too early, so search & some other funct
ion
s were not working immideatly after login (Thx! to Ozan Kulahci)04-July-2002, Vers
ion
0.6[!] Removed Connecting property & OnConnect, OnConnectError, OnDisconnect events. I think there‘s no way of using them. OnConnect
ion
Failed now called when you loose connect
ion
with server or you cannot connect to it.[+]
Add
ed advanced message support(SendMessageAdvanced procedure, OnAdvancedMsgAck event). Now you can receive confirmat
ion
s on messages you‘ve sent![+]
Add
ed SendSMS(const Destinat
ion
, Text: String) procedure for sending sms messages, please, test it and mail me(email above) about results, country where I live isn‘t supported by the ICQ sms gateway :)[+]
Add
ed new items to languages constant array[-] Example wasn‘t showing messages received in RTF format02-July-2002, Vers
ion
0.5[+]
Add
ed visible/invisible list support: look at
Add
ContactVisible,
Add
ContactInvisible funct
ion
s and VisibleList, InvisibleList TStringLists in Help.html file[+] Updated main Example, now it receives server lists, saves contact list to disk and
add
s users from the search dialog[+]
Add
ed new VerySimple example with just logging and sending/receiving messages. This example shows easy of use of the TICQClient component.[+] Changed
Add
Contact(UIN: LongWord) procedute to
Add
Contact(UIN: LongWord): Boolean funct
ion
, it returns True when user is
add
ed to the list and False if it‘s in the list already[+]
Add
ed RemoveContact procedure, which removes UIN from user‘s contact list while you are online[-] Fix in
Add
Contact procedure it was sending the entire contact list, instead of new UIN[-] User‘s info StringLists(Interests, Affiliat
ion
s, etc) in Example having the same group names caused errors: the first group and value were repeated a few times instead of showing the different values with the same groups01-July-2002, Vers
ion
0.4[!] Server side contact list is supported now![+]
Add
ed SendURL(UIN: LongWord; const URL, Descript
ion
: String) procedure for sending URLs[+]
Add
ed SetSelfInfoGeneral, SetSelfInfoMore, SetSelfInfoAbout procedures for uploading the self info[-] Fixed SearchByName procedure, now it works correctly30-June-2002, Vers
ion
0.3[+]
Add
ed ICQClient.dcr icon, thx to Quique![+]
Add
ed OnUserInfoBackground event[-] Fix with user‘s gender in ‘White Pages‘[-] A few other small fixes28-June-2002, Vers
ion
0.2[+]
Add
ed white pages & random search[+] Update to PacketDump viewer (PktDump.pas), not it parses CLI_META and SRV_META packets[-] Fix in SRV_METAINTEREST, interests were badly parsed[-] Some fixes with LNTS strings26-June-2002, Vers
ion
0.1[!] First public release
SSD7 选择题。Multiple-Choice
View Assessment Result: Multiple-Choice Quiz 2 Your performance was as follows: 1. The degree of a table is the number of _____ in the table. (a) keys (b) columns (c) rows (d) foreign keys Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: (b) -------------------------------------------------------------------------------- 2. The arity of a table is the number of _____ in the table. (a) keys (b) columns (c) foreign keys (d) rows Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: (b) -------------------------------------------------------------------------------- 3. What informat
ion
is necessary when specifying the structure of a table? (a) the name of the table and the amount of storage space to be allocated to the table (b) the name of the table, the names of the table's attributes, the data types of the table's attributes, the formats of the table's attributes, and the maximum number of rows that the table can have (c) the name of the table and the names of the table's attributes (d) the name of the table, the names of the table's attributes, the data types of attributes, and the formats of attributes Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: (d) -------------------------------------------------------------------------------- 4. The foreign key in a table T1 _____ the same _____ as the corresponding primary key in table T2. must have, name need not have, name must have, domain (a) I, II, and III (b) I and II (c) I and III (d) II and III Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: (d) -------------------------------------------------------------------------------- 5. Which of the following SQL statements can be used to
add
a row to a table? (a) CREATE (b) INSERT (c) APPEND (d)
ADD
Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: (b) -------------------------------------------------------------------------------- 6. A difference operat
ion
can be applied to tables that (a) are un
ion
compatible (b) have the same column names (c) have the same name (d) are the same size Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: (a) -------------------------------------------------------------------------------- 7. Which of the following SQL statements can be used to create a relat
ion
al table? (a) INSERT (b)
ADD
(c) CREATE (d) APPEND Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: (c) -------------------------------------------------------------------------------- 8. For two tables to be un
ion
compatible, the tables should be the same with respect to which of the following? (a) keys (b) cardinality (c) name (d) degree Correct answer is (d) Your score on this quest
ion
is: 0.00 Feedback: (b) -------------------------------------------------------------------------------- 9. A delet
ion
operat
ion
will _____ if the delet
ion
leads to the
violat
ion
of a referential integrity constraint. (a) fail (b) succeed with warning (c) succeed without warning (d) crash the system Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: (a) -------------------------------------------------------------------------------- 10. With Query By Example, a user enters a query by (a) filling in skeleton tables of the database with examples of what is to be retrieved (b) placing SQL keywords, such as select, under the column names they want to retrieve (c) typing a syntactically correct SQL query that uses column and table names similar to the correct column and table names in a database (d) writing an English descript
ion
of the data that the user needs Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: See sect
ion
1.2.3 in the course notes. (a) -------------------------------------------------------------------------------- Go to top of assessment. Total score: 90.00 ? Copyright 2008 iCarnegie, Inc. All rights reserved. 1. In the Entity-Relat
ion
ship model, the degree of a relat
ion
ship specifies which of the following? (a) The cardinality ratio of the relat
ion
ship (b) The number of integrity constraints required to implement the relat
ion
ship (c) The number of attributes that characterize the relat
ion
ship (d) The number of entities that participate in the relat
ion
ship Correct answer is (d) 2. In an ER model, which of the following is true about a component attribute? (a) A component attribute is always atomic. (b) Component attributes must always be combined by an aggregat
ion
operat
ion
. (c) A component attribute can be a composite attribute. (d) A component attribute always contains other components. Correct answer is (c) 3. In the Entity-Relat
ion
ship model, properties that characterize entities and relat
ion
ships are modeled as (a) attributes (b) participat
ion
constraints (c) entity types (d) weak entities Correct answer is (a) 4. What is an identifying owner in an ER model? (a) The entity upon which a weak entity's existence depends (b) The relat
ion
ship that identifies a weak entity's owner (c) The entity upon which a strong entity's existence depends (d) The relat
ion
ship that identifies a strong entity's owner Correct answer is (a) 5. In an ER model, the cardinality ratio of a relat
ion
ship type is (a) the number of instances of relat
ion
ships of that relat
ion
ship type (b) the number of entity types involved in that relat
ion
ship type (c) the number of relat
ion
ships of that relat
ion
ship type in which an entity can participate (d) the minimum number of entities that can participate in that relat
ion
ship type Correct answer is (c) 6. Which of the following is true about storage for derived attributes? (a) Derived attributes must not be stored. (b) Derived attributes are usually stored because storage improves retrieval performance. (c) Derived attributes must be stored. (d) Derived attributes are usually not stored because they can be computed. Correct answer is (d) 7. In an ER model, what is a recursive relat
ion
ship type? (a) A never-ending type of relat
ion
ship (b) The type of relat
ion
ship that does not belong anywhere (c) The type of relat
ion
ship between entities of one entity type (d) The relat
ion
ship type where the related entities are one and the same Correct answer is (c) 8. In EER modeling, generalizat
ion
is the process of generating (a) superclasses out of subclasses (b) subclasses out of superclasses (c) entities out of attributes (d) attributes out of entities Correct answer is (a) 9. When mapping from an ER model to a relat
ion
al model, a strong entity is mapped into a (a) table (b) row (c) column (d) key Correct answer is (a) 10. Which of the following is true about attributes in a relat
ion
al model? Attributes can be multi-valued. Attributes can be composite. (a) Both I and II (b) II only (c) Neither I nor II (d) I only Correct answer is (c) 1. In an ER model, what is a recursive relat
ion
ship type? (a) The relat
ion
ship type where the related entities are one and the same (b) The type of relat
ion
ship that does not belong anywhere (c) The type of relat
ion
ship between entities of one entity type (d) A never-ending type of relat
ion
ship Correct answer is (c) 2. In an ER model, the cardinality ratio of a relat
ion
ship type is (a) the number of relat
ion
ships of that relat
ion
ship type in which an entity can participate (b) the minimum number of entities that can participate in that relat
ion
ship type (c) the number of entity types involved in that relat
ion
ship type (d) the number of instances of relat
ion
ships of that relat
ion
ship type Correct answer is (a) 3. In the Entity-Relat
ion
ship model, a derived attribute is one (a) that is composed of multiple atomic attributes (b) that characterizes a relat
ion
ship instead of an entity (c) that may have multiple values simultaneously (d) whose value can be computed from the values of other attributes Correct answer is (d) 4. In the Entity-Relat
ion
ship model, properties that characterize entities and relat
ion
ships are modeled as (a) entity types (b) weak entities (c) attributes (d) participat
ion
constraints Correct answer is (c) 5. Which of the following is true about storage for derived attributes? (a) Derived attributes must be stored. (b) Derived attributes are usually stored because storage improves retrieval performance. (c) Derived attributes must not be stored. (d) Derived attributes are usually not stored because they can be computed. Correct answer is (d) 6. What is an identifying owner in an ER model? (a) The relat
ion
ship that identifies a weak entity's owner (b) The relat
ion
ship that identifies a strong entity's owner (c) The entity upon which a strong entity's existence depends (d) The entity upon which a weak entity's existence depends Correct answer is (d) 7. In an ER model, which of the following is true about a component attribute? (a) A component attribute always contains other components. (b) A component attribute can be a composite attribute. (c) A component attribute is always atomic. (d) Component attributes must always be combined by an aggregat
ion
operat
ion
. Correct answer is (b) 8. In EER modeling, generalizat
ion
is the process of generating (a) attributes out of entities (b) superclasses out of subclasses (c) subclasses out of superclasses (d) entities out of attributes Correct answer is (b) 9. When mapping from an ER model to a relat
ion
al model, a strong entity is mapped into a (a) key (b) row (c) column (d) table Correct answer is (d) 10. Which of the following is true about attributes in a relat
ion
al model? Attributes can be multi-valued. Attributes can be composite. (a) I only (b) II only (c) Neither I nor II (d) Both I and II Correct answer is (c) 1. Through normalizat
ion
, update anomalies (a) can be eliminated (b) is usually left unchanged (c) can be maximized (d) can be minimized but not eliminated Correct answer is (a) 2. Which of the following is a property (are properties) exhibited by good relat
ion
al schemas? The use of null values in tuples The grouping of as many attributes as possible into one main table The eliminat
ion
of data redundancy to avoid update anomalies (a) III only (b) None (c) I and II only (d) II and III only Correct answer is (a) 3. Which of the following statements concerning normal forms is true? (a) A relat
ion
that is in second normal form is also in first normal form. (b) The lower the normal form number, the better the schema design is. (c) Each normal form contains a state of independent properties, unrelated to other normal forms. (d) Schemas that are in second normal form are considered the best. Correct answer is (a) 4. Consider the following funct
ion
al dependency. {A, B} -> {C} Regarding this dependency, which of the following statements is (are) true? The values of C are uniquely determined by the values of A. The values of A are uniquely determined by the values of C. (a) None (b) II only (c) I only (d) I and II Correct answer is (a) 5. Which of the following problems can be caused by data redundancy in a relat
ion
al schema? Inefficient use of space Update anomalies and possible loss of data Inefficient use of processing time (a) I and II only (b) I and III only (c) I, II, and III (d) II only Correct answer is (c) 6. Consider a table with atomic attributes A, B, and C and the following funct
ion
al dependencies. A -> B B -> C If the primary key of this table is attribute A, then this relat
ion
satisfies which of the following normal forms? First Second Third (a) None (b) I only (c) I, II and III (d) I and II only Correct answer is (d) 7. For a relat
ion
to be in 3NF, it should not contain _____ attribute that is transitively dependent on _____. (a) a non-primary key, a foreign key (b) a primary key, a non-primary key (c) a primary key, a foreign key (d) a non-primary key, the primary key Correct answer is (d) 8. The FD X -> Y is a full dependency in a relat
ion
R, if there is _____ attribute A that can be _____ X and the dependency still holds. (a) no,
add
ed to (b) no, removed from (c) at least one, removed from (d) at least one,
add
ed to Correct answer is (b) 9. For a relat
ion
to be in 2NF, _____ attribute must be fully funct
ion
ally dependent on _____. (a) every non-primary-key, the primary key (b) every alternate key, the primary key (c) every non-key, every key (d) every non-key, at least one key Correct answer is (a) 10. The FD X -> Y is a partial dependency in a relat
ion
R, if there is _____ attribute A that can be _____ X and the dependency still holds. (a) at least one, removed from (b) at least one,
add
ed to (c) no,
add
ed to (d) no, removed from Correct answer is (a) 1. Through normalizat
ion
, update anomalies (a) can be eliminated (b) is usually left unchanged (c) can be minimized but not eliminated (d) can be maximized Correct answer is (a) 2. Consider the following funct
ion
al dependency. {A, B} -> {C} Regarding this dependency, which of the following statements is (are) true? The values of C are uniquely determined by the values of A. The values of A are uniquely determined by the values of C. (a) None (b) I and II (c) I only (d) II only Correct answer is (a) 3. Which of the following is a property (are properties) exhibited by good relat
ion
al schemas? The use of null values in tuples The grouping of as many attributes as possible into one main table The eliminat
ion
of data redundancy to avoid update anomalies (a) III only (b) None (c) II and III only (d) I and II only Correct answer is (a) 4. Through normalizat
ion
, data redundancy (a) can be eliminated (b) can be maximized (c) can be minimized but not eliminated (d) are usually left unchanged Correct answer is (a) 5. Which of the following statements concerning normal forms is true? (a) A relat
ion
that is in second normal form is also in first normal form. (b) Each normal form contains a state of independent properties, unrelated to other normal forms. (c) Schemas that are in second normal form are considered the best. (d) The lower the normal form number, the better the schema design is. Correct answer is (a) 6. For a relat
ion
to be in 3NF, it should not contain _____ attribute that is transitively dependent on _____. (a) a primary key, a foreign key (b) a primary key, a non-primary key (c) a non-primary key, a foreign key (d) a non-primary key, the primary key Correct answer is (d) 7. The FD X -> Y is a full dependency in a relat
ion
R, if there is _____ attribute A that can be _____ X and the dependency still holds. (a) no, removed from (b) at least one, removed from (c) at least one,
add
ed to (d) no,
add
ed to Correct answer is (a) 8. Consider a table with atomic attributes A, B, and C and the following funct
ion
al dependencies. A -> B B -> C If the primary key of this table is attribute A, then this relat
ion
satisfies which of the following normal forms? First Second Third (a) I, II and III (b) None (c) I and II only (d) I only Correct answer is (c) 9. For a relat
ion
to be in 2NF, _____ attribute must be fully funct
ion
ally dependent on _____. (a) every alternate key, the primary key (b) every non-key, at least one key (c) every non-key, every key (d) every non-primary-key, the primary key Correct answer is (d) 10. The FD X -> Y is a partial dependency in a relat
ion
R, if there is _____ attribute A that can be _____ X and the dependency still holds. (a) no,
add
ed to (b) no, removed from (c) at least one,
add
ed to (d) at least one, removed from Correct answer is (d) 1. What is an identifying owner in an ER model? (a) The entity upon which a weak entity's existence depends (b) The relat
ion
ship that identifies a weak entity's owner (c) The relat
ion
ship that identifies a strong entity's owner (d) The entity upon which a strong entity's existence depends Correct answer is (a) 2. In an ER model, the cardinality ratio of a relat
ion
ship type is (a) the minimum number of entities that can participate in that relat
ion
ship type (b) the number of instances of relat
ion
ships of that relat
ion
ship type (c) the number of entity types involved in that relat
ion
ship type (d) the number of relat
ion
ships of that relat
ion
ship type in which an entity can participate Correct answer is (d) 3. In the Entity-Relat
ion
ship model, properties that characterize entities and relat
ion
ships are modeled as (a) entity types (b) participat
ion
constraints (c) weak entities (d) attributes Correct answer is (d) 4. In an ER model, what is a recursive relat
ion
ship type? (a) A never-ending type of relat
ion
ship (b) The relat
ion
ship type where the related entities are one and the same (c) The type of relat
ion
ship between entities of one entity type (d) The type of relat
ion
ship that does not belong anywhere Correct answer is (c) 5. In the Entity-Relat
ion
ship model, a derived attribute is one (a) that characterizes a relat
ion
ship instead of an entity (b) that may have multiple values simultaneously (c) whose value can be computed from the values of other attributes (d) that is composed of multiple atomic attributes Correct answer is (c) 6. In the Entity-Relat
ion
ship model, the degree of a relat
ion
ship specifies which of the following? (a) The number of attributes that characterize the relat
ion
ship (b) The number of entities that participate in the relat
ion
ship (c) The cardinality ratio of the relat
ion
ship (d) The number of integrity constraints required to implement the relat
ion
ship Correct answer is (b) 7. Which of the following is true about storage for derived attributes? (a) Derived attributes are usually not stored because they can be computed. (b) Derived attributes are usually stored because storage improves retrieval performance. (c) Derived attributes must be stored. (d) Derived attributes must not be stored. Correct answer is (a) 8. In EER modeling, generalizat
ion
is the process of generating (a) superclasses out of subclasses (b) entities out of attributes (c) subclasses out of superclasses (d) attributes out of entities Correct answer is (a) 9. When mapping from an ER model to a relat
ion
al model, a strong entity is mapped into a (a) key (b) table (c) row (d) column Correct answer is (b) 10. Which of the following is true about attributes in a relat
ion
al model? Attributes can be multi-valued. Attributes can be composite. (a) II only (b) I only (c) Both I and II (d) Neither I nor II Correct answer is (d) 1. Which of the following is true about storage for derived attributes? (a) Derived attributes are usually stored because storage improves retrieval performance. (b) Derived attributes must be stored. (c) Derived attributes are usually not stored because they can be computed. (d) Derived attributes must not be stored. Correct answer is (c) 2. In an ER model, the cardinality ratio of a relat
ion
ship type is (a) the minimum number of entities that can participate in that relat
ion
ship type (b) the number of entity types involved in that relat
ion
ship type (c) the number of relat
ion
ships of that relat
ion
ship type in which an entity can participate (d) the number of instances of relat
ion
ships of that relat
ion
ship type Correct answer is (c) 3. In the Entity-Relat
ion
ship model, the degree of a relat
ion
ship specifies which of the following? (a) The number of attributes that characterize the relat
ion
ship (b) The number of integrity constraints required to implement the relat
ion
ship (c) The cardinality ratio of the relat
ion
ship (d) The number of entities that participate in the relat
ion
ship Correct answer is (d) 4. In the Entity-Relat
ion
ship model, properties that characterize entities and relat
ion
ships are modeled as (a) weak entities (b) participat
ion
constraints (c) attributes (d) entity types Correct answer is (c) Your score on this quest
ion
is: 0.00 5. A weak entity type implies a (a) weak relat
ion
ship type (b) relat
ion
ship with total participat
ion
constraint (c) strong relat
ion
ship type (d) relat
ion
ship with partial participat
ion
constraint Correct answer is (b) 6. In an ER model, which of the following is true about a component attribute? (a) A component attribute can be a composite attribute. (b) Component attributes must always be combined by an aggregat
ion
operat
ion
. (c) A component attribute always contains other components. (d) A component attribute is always atomic. Correct answer is (a) 7. In the Entity-Relat
ion
ship model, a derived attribute is one (a) that characterizes a relat
ion
ship instead of an entity (b) that is composed of multiple atomic attributes (c) whose value can be computed from the values of other attributes (d) that may have multiple values simultaneously Correct answer is (c) 1. Through normalizat
ion
, update anomalies (a) is usually left unchanged (b) can be minimized but not eliminated (c) can be maximized (d) can be eliminated Correct answer is (d) 2. Which of the following problems can be caused by data redundancy in a relat
ion
al schema? Inefficient use of space Update anomalies and possible loss of data Inefficient use of processing time (a) I and II only (b) I and III only (c) II only (d) I, II, and III Correct answer is (d) 3. Consider the following funct
ion
al dependency. {A, B} -> {C} Regarding this dependency, which of the following statements is (are) true? The values of C are uniquely determined by the values of A. The values of A are uniquely determined by the values of C. (a) I only (b) I and II (c) II only (d) None Correct answer is (d) 4. Which of the following is a property (are properties) exhibited by good relat
ion
al schemas? The use of null values in tuples The grouping of as many attributes as possible into one main table The eliminat
ion
of data redundancy to avoid update anomalies (a) III only (b) II and III only (c) I and II only (d) None Correct answer is (a) 5. Which of the following statements concerning normal forms is true? (a) Schemas that are in second normal form are considered the best. (b) Each normal form contains a state of independent properties, unrelated to other normal forms. (c) A relat
ion
that is in second normal form is also in first normal form. (d) The lower the normal form number, the better the schema design is. Correct answer is (c) 6. The FD X -> Y is a partial dependency in a relat
ion
R, if there is _____ attribute A that can be _____ X and the dependency still holds. (a) at least one,
add
ed to (b) at least one, removed from (c) no, removed from (d) no,
add
ed to Correct answer is (b) 7. For a relat
ion
to be in 2NF, _____ attribute must be fully funct
ion
ally dependent on _____. (a) every non-primary-key, the primary key (b) every non-key, at least one key (c) every non-key, every key (d) every alternate key, the primary key Correct answer is (a) 8. Consider a table with atomic attributes A, B, and C and the following funct
ion
al dependencies. A -> B B -> C If the primary key of this table is attribute A, then this relat
ion
satisfies which of the following normal forms? First Second Third (a) I only (b) None (c) I and II only (d) I, II and III Correct answer is (c) 9. The FD X -> Y is a full dependency in a relat
ion
R, if there is _____ attribute A that can be _____ X and the dependency still holds. (a) no, removed from (b) at least one, removed from (c) at least one,
add
ed to (d) no,
add
ed to Correct answer is (a) 10. For a relat
ion
to be in 3NF, it should not contain _____ attribute that is transitively dependent on _____. (a) a primary key, a foreign key (b) a non-primary key, a foreign key (c) a non-primary key, the primary key (d) a primary key, a non-primary key Correct answer is (c) 1. Which of the following statements concerning normal forms is true? (a) The lower the normal form number, the better the schema design is. (b) A relat
ion
that is in second normal form is also in first normal form. (c) Schemas that are in second normal form are considered the best. (d) Each normal form contains a state of independent properties, unrelated to other normal forms. Correct answer is (b) 2. Consider the following funct
ion
al dependency. {A, B} -> {C} Regarding this dependency, which of the following statements is (are) true? The values of C are uniquely determined by the values of A. The values of A are uniquely determined by the values of C. (a) I only (b) II only (c) I and II (d) None Correct answer is (d) 3. Which of the following problems can be caused by data redundancy in a relat
ion
al schema? Inefficient use of space Update anomalies and possible loss of data Inefficient use of processing time (a) I, II, and III (b) I and II only (c) I and III only (d) II only Correct answer is (a) Y 4. Through normalizat
ion
, update anomalies (a) can be eliminated (b) can be maximized (c) is usually left unchanged (d) can be minimized but not eliminated Correct answer is (a) 5. Which of the following is a property (are properties) exhibited by good relat
ion
al schemas? The use of null values in tuples The grouping of as many attributes as possible into one main table The eliminat
ion
of data redundancy to avoid update anomalies (a) I and II only (b) III only (c) None (d) II and III only Correct answer is (b) 6. Consider a table with atomic attributes A, B, and C and the following funct
ion
al dependencies. A -> B B -> C If the primary key of this table is attribute A, then this relat
ion
satisfies which of the following normal forms? First Second Third (a) I and II only (b) I only (c) I, II and III (d) None Correct answer is (a) 7. For a relat
ion
to be in 3NF, it should not contain _____ attribute that is transitively dependent on _____. (a) a non-primary key, a foreign key (b) a primary key, a foreign key (c) a primary key, a non-primary key (d) a non-primary key, the primary key Correct answer is (d) 8. The FD X -> Y is a partial dependency in a relat
ion
R, if there is _____ attribute A that can be _____ X and the dependency still holds. (a) at least one,
add
ed to (b) no, removed from (c) no,
add
ed to (d) at least one, removed from Correct answer is (d) 9. For a relat
ion
to be in 2NF, _____ attribute must be fully funct
ion
ally dependent on _____. (a) every non-primary-key, the primary key (b) every alternate key, the primary key (c) every non-key, every key (d) every non-key, at least one key Correct answer is (a) 10. The FD X -> Y is a full dependency in a relat
ion
R, if there is _____ attribute A that can be _____ X and the dependency still holds. (a) no,
add
ed to (b) at least one, removed from (c) at least one,
add
ed to (d) no, removed from Correct answer is (d) 1. In an ER model, which of the following is true about a composite attribute? (a) A composite attribute can have a method attached to it. (b) A composite attribute cannot be broken into more basic attributes. (c) A composite attribute can be broken into more basic attributes. (d) A composite attribute can only be designed by users with special privileges. Correct answer is (c) 2. The term physical data independence refers to the ability to change (a) the physical layout of the data without changing the external schemas, the conceptual schemas, or the applicat
ion
programs (b) the data without physically relocating the tables (c) the conceptual schema without changing the applicat
ion
programs (d) the applicat
ion
programs without changing the conceptual schema Correct answer is (a) 3. What attributes does a subclass have? (a) None of the attributes of its superclass (b) All the attributes of its superclass, and possibly more (c) Just the attributes from the superclass (d) A subset of the attributes of its superclass Correct answer is (b) 4. If X -> Y, which of the following would make Y fully dependent on X? (a) Y is a single attribute (b) X is a single attribute (c) X consists of multiple attributes (d) Y consists of multiple attributes Correct answer is (b) 5. In an ER model, what is the degree of a relat
ion
ship type? (a) The validity of the relat
ion
ship type (b) The strength of the relat
ion
ship type (c) The number of entity types participating in the relat
ion
ship type (d) The number of instances of the relat
ion
ship type Correct answer is (c) 6. Database design typically consists of which of the following phases? Conceptual design Logical design Physical design (a) II only (b) I, II, and III (c) II and III only (d) I only Correct answer is (b) 7. A relat
ion
al schema is in first normal form, if the domain of all of its (a) primary keys are not multi-valued (b) primary keys and alternate keys are not multi-valued (c) primary keys are not composite (d) attributes can take on only atomic values Correct answer is (d) 8. In an ER model, a derived attribute is one whose values (a) have been derived at some time in the past (b) can be derived from the values of some other attributes (c) can be derived from the system tables (d) can be derived from another table Correct answer is (b) 9. Y is transitively dependent on X, if (a) X -> Y and A -> Y (b) X -> A, B and A -> Y (c) X -> Y and Y -> A (d) X -> A, B and Y -> A, B Correct answer is (b) 10. Relat
ion
ships in an ER model are primarily translated to which of the following in a relat
ion
al model? (a) relat
ion
ships (b) primary keys and foreign keys (c) three-way tables (d) dummy relat
ion
ship tables Correct answer is (b) View Assessment Result With Query By Example, a user enters a query by (a) filling in skeleton tables of the database with examples of what is to be retrieved (b) placing SQL keywords, such as select, under the column names they want to retrieve (c) writing an English descript
ion
of the data that the user needs (d) typing a syntactically correct SQL query that uses column and table names similar to the correct column and table names in a database F Your performance was as follows: You took 2 minutes on this assessment from Tue Mar 17 05:22:13 UTC+0800 2009 to Tue Mar 17 05:24:13 UTC+0800 2009. Total score: 100.00 1. An E-Commerce system consists of the following components. Which of the same components must be included in a database management system? 1 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 2 A collect
ion
of programs must be included that control the data, such as programs to create, maintain, and manipulate the data. These programs can be easily used to create, maintain, and manipulate data in other domains, such as in a library informat
ion
system. 3 A collect
ion
of programs that operate on the data, but are specific to the E-commerce system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) II only (b) I, II, and III (c) I only (d) II and III only Correct answer is (a) Your score on this quest
ion
is: 14.29 Feedback: A DBMS refers to just the set of general-purpose programs to control data. (a) 2. An E-Commerce system consists of the following components. Which of these same components will constitute a database system? 4 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 5 A collect
ion
of programs that control the data, such as programs to create, maintain, and manipulate the data constitutes a database system. These programs can be easily used to create, maintain, and manipulate data in other domains such as in a library informat
ion
system. 6 A collect
ion
of programs that operate on the data, but are specific to the E-commerce system, constitutes a database system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) I only (b) I, II, and III (c) I and II only (d) II only Correct answer is (b) Your score on this quest
ion
is: 14.29 Feedback: A database system includes the data, the DBMS, and the applicat
ion
-specific programs that operate on that data. (b) 3. An E-Commerce system consists of the following components. Which of these same components must be included in a database? 7 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 8 A database must include a collect
ion
of programs that control the data, such as programs to create, maintain, and manipulate the data. These programs can be easily used to create, maintain, and manipulate data in other domains. 9 A database must include a collect
ion
of programs that operate on the data, but are specific to the E-commerce system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) I and II only (b) I only (c) II only (d) I, II, and III Correct answer is (b) Your score on this quest
ion
is: 14.29 Feedback: Database refers to just the data (b) 4. An E-Commerce database contains data about customers, products, orders, system response times, etc. Which of the following can be specified as integrity constraints in an E-Commerce database system? 10 No two products can have the same product ID. 11 The DBMS response time for all Web requests should be at most 2 seconds. 12 A customer order cannot have more than one shipping
add
ress
. (a) I and III only (b) I and II only (c) I only (d) I, II, and III Correct answer is (a) Your score on this quest
ion
is: 14.29 Feedback: The constraints I, II and III specify the applicat
ion
semantics of the data captured in the E-Commerce database. Constraint II, although it seems contrary to common sense, is not something that can be prohibited by the DBMS because the DBMS is general purpose. The response time of the DBMS cannot be enforced by the DBMS. It depends on factors such the processor speed, memory available, etc. (a) 5. In a database system, whose responsibility is it to provide data consistency? (a) the user's (b) the applicat
ion
programmer's (c) the DBMS's (d) the database administrator's Correct answer is (c) Your score on this quest
ion
is: 14.29 Feedback: (c) 6. A database is needed for which of the following applicat
ion
scenarios? 13 A video store that needs to keep track of data about members, about videos carried by the store, about videos rented by members, as well as data concerning borrow-date, return-date, and payment informat
ion
. 14 In the human resources department of a company, informat
ion
about employees, their titles, their salaries and sick days, and about vacat
ion
days taken by each employee. 15 A computer-simulated video game which needs to calculate and display, the physical (x, y) locat
ion
of each actor in the game, the speed with which they are moving at the current instant, the direct
ion
in which they are moving, the act
ion
they are performing, the angle at which the game-player is viewing the scene. (a) I only (b) I, II, and III (c) I and II only (d) I and III only Correct answer is (c) Your score on this quest
ion
is: 14.29 Feedback: (c) 7. The physical storage structure will be _____ to the applicat
ion
programmer in a database approach, and will be _____ to the applicat
ion
programmer in a file system approach. (a) hidden, hidden (b) hidden, visible (c) visible, visible (d) visible, hidden Correct answer is (b) Your score on this quest
ion
is: 14.29 Feedback: The layer of abstract
ion
offered by a DBMS hides the physical storage structure from the applicat
ion
programmer. (b) Go to top of assessment. Total score: 100.00 Your performance was as follows: You took 3 minutes on this assessment from Tue Mar 17 04:27:27 UTC+0800 2009 to Tue Mar 17 04:30:02 UTC+0800 2009. Total score: 85.71 1. An E-Commerce system consists of the following components. Which of these same components must be included in a database? 1 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 2 A database must include a collect
ion
of programs that control the data, such as programs to create, maintain, and manipulate the data. These programs can be easily used to create, maintain, and manipulate data in other domains. 3 A database must include a collect
ion
of programs that operate on the data, but are specific to the E-commerce system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) II only (b) I and II only (c) I only (d) I, II, and III Correct answer is (c) Your score on this quest
ion
is: 14.29 Feedback: Database refers to just the data (c) 2. In a database system, whose responsibility is it to provide data consistency? (a) the database administrator's (b) the user's (c) the applicat
ion
programmer's (d) the DBMS's Correct answer is (d) Your score on this quest
ion
is: 14.29 Feedback: (d) 3. An E-Commerce system consists of the following components. Which of these same components will constitute a database system? 4 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 5 A collect
ion
of programs that control the data, such as programs to create, maintain, and manipulate the data constitutes a database system. These programs can be easily used to create, maintain, and manipulate data in other domains such as in a library informat
ion
system. 6 A collect
ion
of programs that operate on the data, but are specific to the E-commerce system, constitutes a database system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) I, II, and III (b) I only (c) I and II only (d) II only Correct answer is (a) Your score on this quest
ion
is: 14.29 Feedback: A database system includes the data, the DBMS, and the applicat
ion
-specific programs that operate on that data. (a) 4. An E-Commerce system consists of the following components. Which of the same components must be included in a database management system? 7 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 8 A collect
ion
of programs must be included that control the data, such as programs to create, maintain, and manipulate the data. These programs can be easily used to create, maintain, and manipulate data in other domains, such as in a library informat
ion
system. 9 A collect
ion
of programs that operate on the data, but are specific to the E-commerce system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) I only (b) I, II, and III (c) II only (d) II and III only Correct answer is (c) Your score on this quest
ion
is: 0.00 Feedback: A DBMS refers to just the set of general-purpose programs to control data. (d) 5. An E-Commerce database contains data about customers, products, orders, system response times, etc. Which of the following can be specified as integrity constraints in an E-Commerce database system? 10 No two products can have the same product ID. 11 The DBMS response time for all Web requests should be at most 2 seconds. 12 A customer order cannot have more than one shipping
add
ress
. (a) I, II, and III (b) I only (c) I and II only (d) I and III only Correct answer is (d) Your score on this quest
ion
is: 14.29 Feedback: The constraints I, II and III specify the applicat
ion
semantics of the data captured in the E-Commerce database. Constraint II, although it seems contrary to common sense, is not something that can be prohibited by the DBMS because the DBMS is general purpose. The response time of the DBMS cannot be enforced by the DBMS. It depends on factors such the processor speed, memory available, etc. (d) 6. A database is needed for which of the following applicat
ion
scenarios? 13 A video store that needs to keep track of data about members, about videos carried by the store, about videos rented by members, as well as data concerning borrow-date, return-date, and payment informat
ion
. 14 In the human resources department of a company, informat
ion
about employees, their titles, their salaries and sick days, and about vacat
ion
days taken by each employee. 15 A computer-simulated video game which needs to calculate and display, the physical (x, y) locat
ion
of each actor in the game, the speed with which they are moving at the current instant, the direct
ion
in which they are moving, the act
ion
they are performing, the angle at which the game-player is viewing the scene. (a) I and II only (b) I only (c) I, II, and III (d) I and III only Correct answer is (a) Your score on this quest
ion
is: 14.29 Feedback: (a) 7. The physical storage structure will be _____ to the applicat
ion
programmer in a database approach, and will be _____ to the applicat
ion
programmer in a file system approach. (a) visible, hidden (b) hidden, hidden (c) hidden, visible (d) visible, visible Correct answer is (c) Your score on this quest
ion
is: 14.29 Feedback: The layer of abstract
ion
offered by a DBMS hides the physical storage structure from the applicat
ion
programmer. (c) Go to top of assessment. Total score: 85.71 Total score: 42.86 1. An E-Commerce system consists of the following components. Which of these same components must be included in a database? 1 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 2 A database must include a collect
ion
of programs that control the data, such as programs to create, maintain, and manipulate the data. These programs can be easily used to create, maintain, and manipulate data in other domains. 3 A database must include a collect
ion
of programs that operate on the data, but are specific to the E-commerce system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) I and II only (b) I only (c) II only (d) I, II, and III Correct answer is (b) Your score on this quest
ion
is: 14.29 Feedback: Database refers to just the data (b) 2. In a database system, whose responsibility is it to provide data consistency? (a) the DBMS's (b) the user's (c) the applicat
ion
programmer's (d) the database administrator's Correct answer is (a) Your score on this quest
ion
is: 0.00 Feedback: (d) 3. An E-Commerce system consists of the following components. Which of these same components will constitute a database system? 4 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 5 A collect
ion
of programs that control the data, such as programs to create, maintain, and manipulate the data constitutes a database system. These programs can be easily used to create, maintain, and manipulate data in other domains such as in a library informat
ion
system. 6 A collect
ion
of programs that operate on the data, but are specific to the E-commerce system, constitutes a database system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) II only (b) I and II only (c) I, II, and III (d) I only Correct answer is (c) Your score on this quest
ion
is: 0.00 Feedback: A database system includes the data, the DBMS, and the applicat
ion
-specific programs that operate on that data. (a) 4. An E-Commerce system consists of the following components. Which of the same components must be included in a database management system? 7 The data, such as informat
ion
about the goods available for sale, customers, orders placed, shipping informat
ion
, etc. 8 A collect
ion
of programs must be included that control the data, such as programs to create, maintain, and manipulate the data. These programs can be easily used to create, maintain, and manipulate data in other domains, such as in a library informat
ion
system. 9 A collect
ion
of programs that operate on the data, but are specific to the E-commerce system. These programs enable users to browse through the store-items, place orders, track shipping, etc. (a) I, II, and III (b) II only (c) I only (d) II and III only Correct answer is (b) Your score on this quest
ion
is: 0.00 Feedback: A DBMS refers to just the set of general-purpose programs to control data. (d) 5. An E-Commerce database contains data about customers, products, orders, system response times, etc. Which of the following can be specified as integrity constraints in an E-Commerce database system? 10 No two products can have the same product ID. 11 The DBMS response time for all Web requests should be at most 2 seconds. 12 A customer order cannot have more than one shipping
add
ress
. (a) I only (b) I and III only (c) I and II only (d) I, II, and III Correct answer is (b) Your score on this quest
ion
is: 0.00 Feedback: The constraints I, II and III specify the applicat
ion
semantics of the data captured in the E-Commerce database. Constraint II, although it seems contrary to common sense, is not something that can be prohibited by the DBMS because the DBMS is general purpose. The response time of the DBMS cannot be enforced by the DBMS. It depends on factors such the processor speed, memory available, etc. (d) 6. A database is needed for which of the following applicat
ion
scenarios? 13 A video store that needs to keep track of data about members, about videos carried by the store, about videos rented by members, as well as data concerning borrow-date, return-date, and payment informat
ion
. 14 In the human resources department of a company, informat
ion
about employees, their titles, their salaries and sick days, and about vacat
ion
days taken by each employee. 15 A computer-simulated video game which needs to calculate and display, the physical (x, y) locat
ion
of each actor in the game, the speed with which they are moving at the current instant, the direct
ion
in which they are moving, the act
ion
they are performing, the angle at which the game-player is viewing the scene. (a) I only (b) I and II only (c) I, II, and III (d) I and III only Correct answer is (b) Your score on this quest
ion
is: 14.29 Feedback: (b) 7. The physical storage structure will be _____ to the applicat
ion
programmer in a database approach, and will be _____ to the applicat
ion
programmer in a file system approach. (a) visible, visible (b) visible, hidden (c) hidden, visible (d) hidden, hidden Correct answer is (c) Your score on this quest
ion
is: 14.29 Feedback: The layer of abstract
ion
offered by a DBMS hides the physical storage structure from the applicat
ion
programmer. (c) Go to top of assessment. The arity of a table is the number of _____ in the table. (a) rows (b) columns (c) keys (d) foreign keys Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 2. The cardinality of a table is the number of _____ in the table. (a) rows (b) foreign keys (c) keys (d) columns Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 3. The degree of a table is the number of _____ in the table. (a) rows (b) columns (c) foreign keys (d) keys Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 4. The foreign key in a table T1 _____ the same _____ as the corresponding primary key in table T2. 1 must have, name 2 need not have, name 3 must have, domain (a) I and III (b) II and III (c) I, II, and III (d) I and II Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 5. The SQL clause to perform a set UN
ION
operat
ion
is (a) MELD (b) UNITE (c) UN
ION
(d) COMBINE Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: 6. DML is used to (a) manipulate the structure of database applicat
ion
s. (b)
add
/modify/delete data in the database. (c) specify the structure of a database. (d)
add
and delete tables. Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 7. DDL is used to (a) specify the structure of a database. (b)
add
contents to tables. (c)
access
the contents of tables. (d) define the structure of database applicat
ion
s. Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 8. Which of the following SQL statements can be used to create a relat
ion
al table? (a) APPEND (b) CREATE (c)
ADD
(d) INSERT Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 9. Which of the following SQL statements can be used to modify just one row (out of many rows) in a table? (a) CHANGE (b) UPDATE (c) ALTER (d) MODIFY Correct answer is (b) Your score on this quest
ion
is: 0.00 Feedback: 10. The term query by example refers to (a) a visual query language developed by IBM (b) a query for SQL examples (c) example SQL queries provided by the DBMS that users can modify to suit their current needs (d) example SQL queries provided by other users that can be modified to suit current needs Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: See sect
ion
1.2.3 in the course notes. Your performance was as follows: You took 4 minutes on this assessment from Wed Mar 29 08:46:41 UTC+0800 2006 to Wed Mar 29 08:50:36 UTC+0800 2006. Total score: 90.00 1. What informat
ion
is necessary when specifying the structure of a table? (a) the name of the table, the names of the table's attributes, the data types of attributes, and the formats of attributes (b) the name of the table, the names of the table's attributes, the data types of the table's attributes, the formats of the table's attributes, and the maximum number of rows that the table can have (c) the name of the table and the names of the table's attributes (d) the name of the table and the amount of storage space to be allocated to the table Correct answer is (a) Your score on this quest
ion
is: 0.00 Feedback: 2. The cardinality of a table is the number of _____ in the table. (a) columns (b) foreign keys (c) rows (d) keys Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: 3. The arity of a table is the number of _____ in the table. (a) foreign keys (b) keys (c) rows (d) columns Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 4. The degree of a table is the number of _____ in the table. (a) rows (b) foreign keys (c) columns (d) keys Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: 5. A difference operat
ion
can be applied to tables that (a) are un
ion
compatible (b) have the same name (c) are the same size (d) have the same column names Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 6. Which of the following SQL statements can be used to remove a row from a table? (a) DESTROY (b) DELETE (c) ERASE (d) REMOVE Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 7. DML is used to (a)
add
/modify/delete data in the database. (b)
add
and delete tables. (c) manipulate the structure of database applicat
ion
s. (d) specify the structure of a database. Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 8. A delet
ion
operat
ion
will _____ if the delet
ion
leads to the
violat
ion
of a referential integrity constraint. (a) fail (b) succeed with warning (c) succeed without warning (d) crash the system Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 9. DDL is used to (a)
access
the contents of tables. (b)
add
contents to tables. (c) define the structure of database applicat
ion
s. (d) specify the structure of a database. Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 10. With Query By Example, a user enters a query by (a) writing an English descript
ion
of the data that the user needs (b) typing a syntactically correct SQL query that uses column and table names similar to the correct column and table names in a database (c) filling in skeleton tables of the database with examples of what is to be retrieved (d) placing SQL keywords, such as select, under the column names they want to retrieve Correct answer is (c) Your score on this quest
ion
is: 10.00 1. What informat
ion
is necessary when specifying the structure of a table? (a) the name of the table, the names of the table's attributes, the data types of attributes, and the formats of attributes (b) the name of the table, the names of the table's attributes, the data types of the table's attributes, the formats of the table's attributes, and the maximum number of rows that the table can have (c) the name of the table and the names of the table's attributes (d) the name of the table and the amount of storage space to be allocated to the table Correct answer is (a) Your score on this quest
ion
is: 0.00 Feedback: 2. The cardinality of a table is the number of _____ in the table. (a) columns (b) foreign keys (c) rows (d) keys Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: 3. The arity of a table is the number of _____ in the table. (a) foreign keys (b) keys (c) rows (d) columns Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 4. The degree of a table is the number of _____ in the table. (a) rows (b) foreign keys (c) columns (d) keys Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: 5. A difference operat
ion
can be applied to tables that (a) are un
ion
compatible (b) have the same name (c) are the same size (d) have the same column names Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 6. Which of the following SQL statements can be used to remove a row from a table? (a) DESTROY (b) DELETE (c) ERASE (d) REMOVE Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 7. DML is used to (a)
add
/modify/delete data in the database. (b)
add
and delete tables. (c) manipulate the structure of database applicat
ion
s. (d) specify the structure of a database. Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 8. A delet
ion
operat
ion
will _____ if the delet
ion
leads to the
violat
ion
of a referential integrity constraint. (a) fail (b) succeed with warning (c) succeed without warning (d) crash the system Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 9. DDL is used to (a)
access
the contents of tables. (b)
add
contents to tables. (c) define the structure of database applicat
ion
s. (d) specify the structure of a database. Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 10. With Query By Example, a user enters a query by (a) writing an English descript
ion
of the data that the user needs (b) typing a syntactically correct SQL query that uses column and table names similar to the correct column and table names in a database (c) filling in skeleton tables of the database with examples of what is to be retrieved (d) placing SQL keywords, such as select, under the column names they want to retrieve Correct answer is (c) The cardinality of a table is the number of _____ in the table. (a) rows (b) keys (c) foreign keys (d) columns Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 2. The foreign key in a table T1 _____ the same _____ as the corresponding primary key in table T2. 1 must have, name 2 need not have, name 3 must have, domain (a) I and II (b) I, II, and III (c) II and III (d) I and III Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: 3. What informat
ion
is necessary when specifying the structure of a table? (a) the name of the table and the names of the table's attributes (b) the name of the table, the names of the table's attributes, the data types of attributes, and the formats of attributes (c) the name of the table, the names of the table's attributes, the data types of the table's attributes, the formats of the table's attributes, and the maximum number of rows that the table can have (d) the name of the table and the amount of storage space to be allocated to the table Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 4. The arity of a table is the number of _____ in the table. (a) columns (b) foreign keys (c) keys (d) rows Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 5. A difference operat
ion
can be applied to tables that (a) are un
ion
compatible (b) are the same size (c) have the same name (d) have the same column names Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 6. What can be specified in the select
ion
condit
ion
of a SELECT statement? (a) a Boolean operat
ion
(b) an arithmetic operat
ion
(c) the condit
ion
s under which the statement should be executed (d) the time at which the select
ion
should be performed Correct answer is (a) Your score on this quest
ion
is: 0.00 Feedback: 7. The SQL clause to perform a set UN
ION
operat
ion
is (a) MELD (b) UN
ION
(c) UNITE (d) COMBINE Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 8. Which of the following SQL statements can be used to
add
a row to a table? (a) APPEND (b) CREATE (c)
ADD
(d) INSERT Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 9. A join operat
ion
joins _____ tables into _____. (a) two, one (b) four, two (c) three, one (d) three, two Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: 10. With Query By Example, a user enters a query by (a) placing SQL keywords, such as select, under the column names they want to retrieve (b) writing an English descript
ion
of the data that the user needs (c) typing a syntactically correct SQL query that uses column and table names similar to the correct column and table names in a database (d) filling in skeleton tables of the database with examples of what is to be retrieved Correct answer is (d) Your score on this quest
ion
is: 10.00 The degree of a table is the number of _____ in the table. (a) foreign keys (b) columns (c) rows (d) keys Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 2. The arity of a table is the number of _____ in the table. (a) rows (b) keys (c) columns (d) foreign keys Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: 3. What informat
ion
is necessary when specifying the structure of a table? (a) the name of the table and the amount of storage space to be allocated to the table (b) the name of the table and the names of the table's attributes (c) the name of the table, the names of the table's attributes, the data types of the table's attributes, the formats of the table's attributes, and the maximum number of rows that the table can have (d) the name of the table, the names of the table's attributes, the data types of attributes, and the formats of attributes Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 4. The cardinality of a table is the number of _____ in the table. (a) foreign keys (b) columns (c) keys (d) rows Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 5. DML is used to (a) specify the structure of a database. (b)
add
and delete tables. (c) manipulate the structure of database applicat
ion
s. (d)
add
/modify/delete data in the database. Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 6. The SQL clause to perform a set UN
ION
operat
ion
is (a) COMBINE (b) UN
ION
(c) UNITE (d) MELD Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 7. Which of the following SQL statements can be used to create a relat
ion
al table? (a)
ADD
(b) APPEND (c) CREATE (d) INSERT Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: 8. DDL is used to (a)
access
the contents of tables. (b) specify the structure of a database. (c)
add
contents to tables. (d) define the structure of database applicat
ion
s. Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: 9. What can be specified in the select
ion
condit
ion
of a SELECT statement? (a) the time at which the select
ion
should be performed (b) an arithmetic operat
ion
(c) the condit
ion
s under which the statement should be executed (d) a Boolean operat
ion
Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: 10. The term query by example refers to (a) a query for SQL examples (b) example SQL queries provided by other users that can be modified to suit current needs (c) a visual query language developed by IBM (d) example SQL queries provided by the DBMS that users can modify to suit their current needs Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: See sect
ion
1.2.3 in the course notes. Go to top of assessment. Your performance was as follows: 1. What informat
ion
is necessary when specifying the structure of a table? (a) the name of the table, the names of the table's attributes, the data types of attributes, and the formats of attributes (b) the name of the table and the amount of storage space to be allocated to the table (c) the name of the table and the names of the table's attributes (d) the name of the table, the names of the table's attributes, the data types of the table's attributes, the formats of the table's attributes, and the maximum number of rows that the table can have Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: (a) 2. The foreign key in a table T1 _____ the same _____ as the corresponding primary key in table T2. 1 must have, name 2 need not have, name 3 must have, domain (a) I and II (b) II and III (c) I and III (d) I, II, and III Correct answer is (b) Your score on this quest
ion
is: 10.00 Feedback: (b) 3. The arity of a table is the number of _____ in the table. (a) foreign keys (b) rows (c) keys (d) columns Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: (d) 4. The cardinality of a table is the number of _____ in the table. (a) keys (b) columns (c) rows (d) foreign keys Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: (c) 5. Which of the following SQL statements can be used to create a relat
ion
al table? (a) INSERT (b)
ADD
(c) CREATE (d) APPEND Correct answer is (c) Your score on this quest
ion
is: 10.00 Feedback: (c) 6. The SQL clause to perform a set difference operat
ion
is (a) EXCEPT (b) OMIT (c) DIFFER (d) REJECT Correct answer is (a) Your score on this quest
ion
is: 10.00 Feedback: (a) 7. Which of the following SQL statements can be used to remove a row from a table? (a) ERASE (b) REMOVE (c) DESTROY (d) DELETE Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: (d) 8. Which of the following SQL statements can be used to
add
a row to a table? (a)
ADD
(b) APPEND (c) CREATE (d) INSERT Correct answer is (d) Your score on this quest
ion
is: 10.00 Feedback: (d) 9. What can be specified in the select
ion
condit
ion
of a SELECT statement? (a) the time at which the select
ion
should be performed (b) a Boolean operat
ion
(c) an arithmetic operat
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