INFORMATICS PRACTICES

50 QUESTIONS

Q1.WhatisMACAddress?

Ans:Incomputernetworking,aMediaAccessControladdress(MAC)isauniqueidentifierassignedtomostnetworkadaptersornetworkinterfacecards(NICs)bythemanufacturerforidentification,andusedintheMediaAccessControlprotocolsub-layer.

Q2.Writetwoadvantagesofnetworks.

Ans: Advantages:i) Dataorinformationcanbesharedamongtheusers.

ii) Fastcommunicationcanbeachieved.

Q3.Writetwodisadvantagesofnetworks.

Ans:Disadvantagesofnetworks:

i.SophisticatedHardwareandsoftwaretechnologyisrequired.

ii.Expensivetoinstallnetwork.

Q4.Whatiscommunicationchannel?Namethebasictypesofcommunicationchannelsavailable.

Ans:Whatiscommunicationchannel?Namethebasictypesofcommunicationchannelsavailable.

Communication channelsmeantheconnectingcables thatlinkvarious workstations. There are3basictypesofcables:

Q5.Defineanetwork.

•TwistedPaircables

•Coaxialcables

•Fiber-opticcables

Ans:Acomputernetworkisasysteminwhichcomputersareconnectedtoshareinformationandresources.

Q6.WhatisIPaddress?

AnsAuniquenumberconsistingof4partsseparatedbydots,e.g.165.113.245.2EverymachinethatisontheInternethasauniqueIPnumber-ifamachinedoesnothavean IPnumber,itisnotreallyonthe Internet.

Q7.Whatisdomainname? Howisitalternativelyknown?

AnsTheuniquenamethatidentifiesanInternetsite.DomainNamesalwayshave2ormoreparts,separatedbydots.Thepartontheleftisthemostspecific,andtheparton therightisthemostgeneral.E.g.:matisse.net

Q1.WhatisOSS?

QuestionsandAnswer

AnsOpenSourceSoftwareisasoftwareavailablewithsourcecodeandfreetochange/edit/redistributeandimposednofurtherrestrictionsonproductoritsusage.

Q2.Expandtheterms:OSI,FLOSS,FSF,GNU,W3C,andPHP.

Ans:OSI: Opensource Initiative

FLOSS:FreeLibreandOpenSourceSoftware.

FSF:FreesoftwareFoundationcreatedforthepurposeofsupportingfreeMovement.

GNU:GNU’s Not Unix Project established with anobjective to create a systemCompatibletoUNIXbutnotidenticalwithit.

W3C:World Wide WEB consortium is responsible for producing the softwarestandardsforWorldWideWeb.

PHP:HypertextPre-processorisawidelyusedopensourceprogramminglanguageprimarilyforserversideapplicationsanddevelopingdynamicwebcontent.

Q3.Whatisfreesoftware?

Ans:FreeSoftwaremeansthesoftwareisfreelyaccessibleandcanbefreelyused,changed,improved,copiesanddistributedtoothers.

Q4.Definefreewareandshareware.

AnsThefreewareisthesoftwareavailablefreeofcostandallowscopyingandfurtherdistributionbutdoesnotallowsmodificationasitssourcecodeisnotavailable.

Sharewareisassoftwarewhichisavailableforredistributionforstipulatedtimebutaftersometimesomelicensefeeisrequiredtobepaid.

Q7.Whataredifferentfontcategories?

Ans:Therearetwocategoriesoffont:TrueTypeFontandOpenTypeFont.

TrueTypeFont:ItisdevelopedbyAppleandlicensedtoMicrosoft.Itis8bitfontwhichiscompatiblewithMicrosoftWindowsandMACOS.

OpenTypeFont:ItistheextensionoftheTrueTypeFontFormatwhichis16bitsfonandsupport65536characters(Unicodecharacters).

Q10.WhatisUnicode?

Ans10:Unicodeprovidesauniquenumberforeverycharacter,nomaterwhattheplatforms,nomatterwhattheprogram,nomatterwhatthelanguage.Unicodecanrepresent94140characters.

Q11.WhatisISCII?

Ans:IndianStandardCodeforInformationInterchange(ISCII)isacoding schemefor representingvariouswritingsystemsofIndia.ItencodesthemainIndicscriptsandaRomantransliteration.Whenwe typeIndianLanguage wordsphoneticallyinEnglishscriptandtoolwillautomaticallyconvertthemintocorrespondinglanguagewordscalledastransliteration.

Q20Findtheoutputofthefollowingcodesnippetwritteninjavapublicstaticvoidmain(String[

]args)

{

longa=78345,s1=0,s2=0,r;while(a>0)

{

r=a%10;

if(r%4==0)s1+=r;

elses2+=r;a/=10;

}

System.out.println("S1="+s1);System.out.println("S2="+s2);

}

Ans.Output:

s1=12

s2=15

Q21.CorrecttheerrorsinthefollowingprogramsegmentwritteninJAVA.Youarejustrequiredtowritethecorrectedcode,underlyingthecorrectionsmade.

publicStaticVoidMain(String[]args)

{

IntegerNos=100;while(Nos=45)

{

If(Nos%5=0);Nos+=10;

otherwiseNos+=20;

}

}

Ans:CorrectedCode

publicstaticvoidmain(String[]args)

{

intNos=100;while(Nos=45)

Chapter-4

1.WhatwouldbethenameoftheeventhandlermethodintheListSelectionlistenerinterfaceforalistnamelyCheckListtohandleitsitemselections?

a.CheckListValueChanged()b.getSelectedValue()c.clearSelection()Ans:a.CheckListValueChanged()

2.Whichcontroldisplaystextthattheusercannotdirectlychangeoredit?a.TextFieldb.Checkboxc.Comboboxd.Label

Ans:d.Label

3.Whichcontrolprovidesbasictexteditingfacility?a.TextFieldb.Checkboxc.Comboboxd.Label

Ans:a.TexfField

4.Occurrenceofanactivityiscalled:

a.Functionb.Classc. Objectd.EventAns:d.Event.

5.WhichpropertyisusedtosetthetextoftheLabel?

a.fontb.textc.named.iconAns:b.text

6.Theobjectcontainingthedatatobeexhibitedbythecomboboxbywhichproperty.

a.editableb.modelc.selectedIndexd.selectedItemAns:b.model

7.WhatisGUIprogramming?

Ans:AGUI(GraphicalUser Interface)isaninterfacethatusespicturesandothergraphicentitiesalongwithtext,tointeractwithuser.

8.HowisswingrelatedtoGUIprogramming?

Ans:WecancreateaGUIapplicationonJavaplatformusingSwingAPI(ApplicationProgrammingInterface),whichispartofJavaFoundationClasses(JFC).

9.Whatisanevent?Whatiseventhandler?

Ans:Aneventisoccurrenceofsomeactivitieseitherinitiatedbyuserorbythesystem.Inordertoreact,youneedtoimplementsomeEventhandlingsysteminyourApplication.ThreethingsareimportantinEvenHandling-

EventSource:ItistheGUIcomponentthatgeneratestheevent,e.g.Button.

EventHandlerorEventListener:Itisimplementedasintheformofcode.ItreceivesandhandleseventsthroughListenerInterface.

EventObjectorMessage:Itiscreatedwheneventoccurs.ItcontainsalltheinformationabouttheeventwhichincludesSourceofeventandtypeof

eventetc.

10.WhatisthedefaultnameofactioneventhandlerofabuttonnamelyTestBtn?Ans:privatevoidTestBtnActionPerfomed(java.awt.action.ActionEventevt){}.

11.Whatpropertywouldyousettoassignaccesskeytoabutton?

Ans:mnemonicpropertyisusedtoassignaccesskeyorshortcut(Alt+Key).

12.Whichmethodcanprogrammaticallyperformstheclickactionofapushbutton?Ans:privatevoidTestBtnActionPerfomed(java.awt.action.ActionEventevt){}.

13.Whichpropertywouldyousetthesettingthepasswordcharacteras‘$’?Ans:echoChar

14.Whichmethodreturnsthepasswordenteredinapasswordfield?Ans:char[]getPassword().

15.Whichlistpropertydoyousetforspecifyingtheitemsforthelist.Ans:model

16.Whichmethodwouldyouusetodeterminetheindexofselectediteminalist?Ans:intgetSelectedIndex().

17.Whichmethodwouldyouusetoinsertanitematspecifiedindex,inthelist?Ans:voidsetSelectedIndex(intindex).

18.Howyoucandeterminewhether5thiteminalistisselectedornot?Ans:isSelectedIndex(4).

19.Whichmethodyouwouldusetoinsert‘Hello’at10thpositionintheTextAreacontrol.Ans:voidinsert(“Hello”,9).

20.WhichmethodyouwouldliketousetoinsertanIcon(picture)onaPushButton.Ans:voidsetIcon(Icon).

21.WhichpropertywouldyouliketosettomakeaComboboxeditable?Ans:editable.

22.WhatisLayoutManager?NamethelayoutmanagersofferedbyNetBeans?

Ans:LayoutmanagersenableyoutocontrolthewayinwhichvisualcomponentsarearrangedinGUIformsbydeterminingthesizeandpositionofcomponentswithincontainers.

Thereareseventypesoflayoutareavailable–

•FlowLayout

•GridLayout

•CardLayout

•SpringLayout

•BorderLayout

•GridBagLayout

•BoxLayout

23.Namethreecommonlyusedpropertiesandmethodsofthefollowingcontrols.

(a)textfield(b)textarea(c)CheckBox

Ans:(a)Properties:text,font,editable.Methods:voidsetText(),StringgetText(),voidsetEditable(boolean).

(b)Properties:enabled,editable,wrapStyleWordMethods:setText(),getText(),isEditable()

(c)Properties:font,text,selected.Methods:getText(),isEnabled(),isSelected().

24.Whatisdispose()usedfor?

Ans:dispose()isusedforhideanddisposeoftheframewhentheuserclosesit.Thisremovestheframefromthescreenandfreesupanyresourcesusedbyit.

25.Whatisthedifferencebetween-

(a)TextfieldTextarea

(b)Textfieldpasswordfield

(c)RadioButtonCheckBox

Ans:(a)Atextfield’stextpropertycanholdsinglelineoftextunlessitisanHTMLtext.Whileatextarea’stextcanholdanynumberoflinesoftextdependinguponitsrowsproperty.

(b)Thoughatextfieldandapasswordfieldcanobtainasinglelineoftextfromtheuser,yetthesearedifferent.

Apasswordfielddisplaystheobtainedtextinencryptedformonscreenwhiletextfielddisplaystheobtainedtextinunencryptedform.

(c)RadioButton:AjRadioButtoncontrolbelongstoJRadioButtonclassofSwingcontrols. Itisusedtogetchoicesfromtheuser.Itisgroupedcontrol,sothatonlyonecanbeselectedatatimeamongthem.RadioButtonworksingroup,sothattheymustbekeptinaButtonGroupcontainercontrollikesothatonlyonecanbeselectedatthesametime.

SomefeaturesofjRadioButtoncontrolare-

YItcan beused toinput choicestypedinput totheapplication.

YOnlyoneRadiobuttoncanbeselectedatatime.

YTheymustbekeptinaButton Groupcontainer controlto formagroup.

Checkbox:AjCheckBoxcontrolbelongstoJCheckBoxclassofSwingcontrols.Itindicateswhether

aparticularconditionisonoroff.YoucanuseCheckboxestogiveuserstrue/falseoryes/nooptions.CheckBoxesmayworksindependentlytoeachother,sothatanynumberofcheckboxescanbeselectedatthesametime.

SomefeaturesofjCheckBoxcontrolare-

YItcanbeusedtoinputTrue/FalseorYes/Notypedinputtotheapplication.

YMultiplecheckboxescanbeselectedatthesametime.

26.Whatisthesignificanceoffollowingpropertiesofatextarea?

(a)lineWrap(b)wrapStyleword

Ans:(a)DefinesWrappingfeatureenable/disable(b)Determineswherelinewrappingoccurs. Iftrue,thecomponentattemptstowraponlyatwordboundaries.Thispropertyisignoredunlesslinewrapissettotrue.

27.Whatisthesignificanceofabuttongroup? Howdoyoucreateabutton group?

Ans:WemustaddaButtonGroupcontroltotheframeto groupthecheckboxesbyusingButtonGrouppropertyofthecheckbox.Bydraggingbuttongroupcontrolfrompalettewindow.

28.CreateaJavaDesktopApplicationtofindtheincentive(%)ofSalesforaSalesPersononthebasisoffollowingfeedbacks:

Feedback / Incentive(%)
MaximumSales
ExcellentCustomerFeedbackMaximumCountCustomer / 10
8
5

Note:thatthesalesentryshouldnotbespace.Calculatethetotalincentiveas:Salesamount*Incentive.ThefeedbackwillbeimplementedinJCheckBoxcontrols.UsingaJButton’s(ComputeIncentive) clickeventhandler,displaythetotalincentivesinaJTextFieldcontrol.Assumethenomenclatureof theswingcomponentsofyourown.

NotethattheJFramefromIDEwindowwillbeshownas given:

Ans:-privatevoidbtnIncActionPerformed(java.awt.ActionEventevt){intsales=0;

if(!txtSales.getText().trim().equals(“”)){

sales-Integer.parseInt(txtSales.getText().trim());

}

doubleincentive=0.0;

if(jCheckBox1.isSelected()){incentive=incentive+0.1;

}

if(jCheckBox2.isSelected()){incentive=incentive+0.8;

}

if(jCheckBox3.isSelected()){incentive=incentive+0.05;

}

txtInc.setText(““+Math.round(sales*incentive));

}

29.AssumethefollowinginterfacebuiltusingNetbeansusedforbillcalculationofaice-creamparlor.Theparloroffersthreeveritiesofice-cream–vanilla,strawberry,chocolate.VanillaicecreamcostsRs.30,StrawberryRs.35andChocolateRs.50.Acustomercanchoseoneor

moreice-creams,withquantitiesmorethanoneforeachofthevarietychosen.Tocalculatethebillparlormanagerselectstheappropriatecheckboxesaccordingtotheveritiesofice-creamchosenbythecustomerandentertheirrespectivequantities.

WriteJavacodeforthefollowing:

a.Ontheclickeventofthebutton‘Calculate’,theapplicationfindsanddisplaysthetotalbillofthecustomer.Itfirstdisplaystherateofvariousice-creamsintherespectivetextfields. Ifauserdoesn’tselectacheckbox,therespectiveice-creamratemustbecomezero.Thebilliscalculatedbymultiplyingthevariousquantitieswiththeirrespectiverateandlateraddingthemall.

b.OntheClickeventoftheclearbuttonallthetextfieldsandthecheckboxesgetcleared.

c.Ontheclickeventoftheclosebuttontheapplicationgetsclosed.

Ans:(a)

privatevoidjBtncalculateActionPerformed(java.awt.event.ActionEventevt)

{

if(jchkStrawberry.isSelected()==true)jTxtPriceStrawberry.setText("35");else

{

jTxtPriceStrawberry.setText("0");jTxtQtyStrawberry.setText("0");

}

if(jChkChocolate.isSelected()==true)jTxtPriceChocolate.setText("50");else

{

jTxtPriceChocolate.setText("0");jTxtQtyChocolate.setText("0");

}

if(jChkVinella.isSelected()==true)jtxtPriceVinella.setText("30");else

{

jtxtPriceVinella.setText("0");jTxtQtyVinella.setText("0");

}

intr1,r2,r3,q1,q2,q3,a1,a2,a3,gt;r1=Integer.parseInt(jTxtPriceStrawberry.getText());r2=Integer.parseInt(jTxtPriceChocolate.getText());r3=Integer.parseInt(jtxtPriceVinella.getText());q1=Integer.parseInt(jTxtQtyStrawberry.getText());q2=Integer.parseInt(jTxtQtyChocolate.getText());q3=Integer.parseInt(jTxtQtyVinella.getText());a1=r1*q1;

jTxtAmtStrawberry.setText(""+a1);a2=r2*q2;jTxtAmtChocolate.setText(""+a2);a3=r3*q3;jTxtAmtVinella.setText(""+a3);gt=a1+a2+a3;jTxtTotalAmt.setText(""+gt);

}

Ans.(b)

privatevoidjBtnClearActionPerformed(java.awt.event.ActionEventevt)

{

jTxtPriceStrawberry.setText("");jTxtPriceChocolate.setText("");jtxtPriceVinella.setText("");jTxtQtyStrawberry.setText("");jTxtQtyChocolate.setText("");jTxtQtyVinella.setText("");jTxtAmtStrawberry.setText("");jTxtAmtChocolate.setText("");jTxtAmtVinella.setText("");jchkStrawberry.setSelected(false);jChkChocolate.setSelected(false);jChkVinella.setSelected(false);

}

Ans:(c)

privatevoidjBtncloseActionPerformed(java.awt.event.ActionEventevt)

{

System.exit(0);

}

{

if(Nos%5==0)_Nos+=10;

else

Nos+=20;

}

}

HTML AND XML

SolvedQuestions:

1.Identifythewebbrowsersoftwarefromthefollowingoptions:

(a)ApacheWebServer(b)MSWord(c)HTML(d)MozillaFirefox

Ans.(d)MozillaFirefox

2.Adocumentiscreatedbywebserverwheneverabrowserrequeststhedocuments.

(a)active(b)static(c)dynamic(d)noneoftheabove

Ans.(c)Dynamic

3.Adocumentisafixedcontentdocumentthatiscreatedbywebserverwheneverabrowserrequeststhedocuments.

(a)active(b)static(c)dynamic(d)noneoftheabove

Ans.(b)Static

4.Identifythewebserversoftwarefromthefollowingoptions:

(a)Apache(b)MSWord(c)HTML(d)MozillaFirefox

Ans.(a)Apache

5.Theaddressofaresourceonthenetisknownas:

(a)ISP(b)HTTP(c)URL(d)WWW

Ans.(c)URL

6.AprogramthatservesrequestedHTMLfilesandpages.

(a)WebAddress(b)WebPage(c)WebServer(d)Noneofthese

Ans.(c)WebServer

7.WhatisUniformResourceLocator?

Ans:Theuniformresourcelocator(URL)istheuniqueidentifierofawebpage.Theaddress orURLofthecurrentpageyouareonappearsinthe"AddressBar"ofthewebbrowser.Youcan godirectlytoawebpageifyouknowitsURLbysimplytypingtheURLintheaddress bar.YoucanclickintheaddressbaratanytimeandoverwritethecurrentaddresswithanotherURLtojumptoadifferentwebpage.ThemostgeneralformofaURLsyntaxisasfollows:

Protocol://domainname/directorypath/objectname Forexample:

8.WhatisWebServer?

Ans:Webserverdelivers(serves)content,suchaswebpages,usingtheHypertextTransferProtocol(HTTP),overtheWorldWideWeb.

9.WhatisWebBrowser?

Ans:Awebbrowserisaclientthatinitiatescommunicationbymakingarequestforaspecificresource.Theserverthenrespondswiththecontentofthatresource,oranerrormessageifunabletodoprovidethecontentsduetoanyreason.

1.HTMLtagsmustbewrittenwithin:

(a)(b){} (c)[ ] (d)()

Ans:(a)

2.WhichofthefollowingisthecorrectstructureofHTMLtags?

(a)HTML/HTML<HEAD/HEADBODY/BODY

(b)<HTML<HEAD/HEAD/HTMLBODY/BODY

(c)HTML<HEADBODY/BODY/HEAD/HTML

(d)<HTML<HEAD/HEADBODY/BODY/HTML

Ans:(d)<HTMLHEAD/HEADBODY/BODY/HTML

3.WhatisHTML?

Ans:HTMLstandsforHyperTextMarkup Language.ItisamarkuplanguageusedtocreateHTMLdocuments.AnHTMLdocumentdefinesawebpage.

4.Definehtml>tag

Ans:Thehtml>tagidentifiesthedocument.AnHTMLdocumentbeginwithhtml>endswith

/html.

5.GivetwodifferencesbetweenHTMLandXML.

Ans:ThethreedifferencesbetweenHTMLandXMLare:

1.HTMLisdesignedtodisplaydataandhence,focussedonthe‘look’ofthedata,whereasXMLisdesignedtodescribeandcarrydataandhence,focuseson‘whatdatais’.

2.InHTMLtagsarepredefined,whileinXML,tagscanbecreatedasperneeds.

3.HTMLtagsarenotcasesensitive,whereasXMLtagsarecasesensitive

1.CompareHTMLandXMLbrieflyAns.- HTMLversu XML

CHAPTER14

MYSQLREVISIONTOUR

1.Whatisdifferencebetweencharandvarchar?

Ans-Thedifferencebetweencharandvarcharisthatoffixedlength and variable length.TheCHARdatatypesspecifiesafixedlengthcharacterstring.WhenacolumnisgivendatatypeasCHAR(n)thenMySQLensuresthatallvaluesstoredinthatcolumnhavethislength.ButonotherhandwhenacolumnisgivendatatypeasVARCHAR(n),thenthemaximumsizeofavalueinthiscolumnstoresexactlywhatwespecify.

2.Whatdoyouunderstandbythetermsprimarykeyanddegreeofarelationinrelationaldatabase?

Ans:PrimaryKey:Aprimarykeyisasetofoneormoreattributesthatcan uniquelyidentifytupleswithintherelations.ThenumberofattributesinarelationiscalledDegreeofarelationinrelationaldatabase.

3.Whatdoyouunderstandbythecandidatekeyandcardinalityofarelationinrelationaldatabase?

CandidateKey:Allattributecombinationsinsidearelationthatcanserveasprimarykey(uniquelyidentifiesarowinarelation)areCandidateKeysastheyarecandidatesfortheprimarykeyposition.Thenumberofrowsinarelationisknownascardinalityofarelation.

4.ConsiderthefollowingtablesItemandCustomer.WriteSQLcommandsforthestatement

(i)to(iv)andgiveoutputsforSQLqueries(v)to(viii)Table:ITEM

Table:CUSTOMERC_IDCustomerNameCityI_ID

S.no / CUSTOMER
C_ID / CustomerName / City / I_ID
01 / 01 / N.Roy / Delhi / LC03
02 / 06 / H.Singh / Mumbai / PC03
03 / 12 / R.Pandey / Delhi / PC06
04 / 15 / C.Sharma / Delhi / LC03
05 / 16 / K.Agrawal / Bangalore / PC01

(i)TodisplaythedetailsofthoseCustomerswhosecityisDelhi

.Ans:SelectallfromCustomerWhereCity=”Delhi”

(ii)TodisplaythedetailsofItemwhosePriceisintherangeof35000to55000(Bothvaluesincluded).

Ans:SelectallfromItemWherePrice=35000andPrice<=55000

(iii)TodisplaytheCustomerName,CityfromtableCustomer,andItemNameandPricefromtableItem,withtheircorrespondingmatchingI_ID.

Ans:SelectCustomerName,City,ItemName,PricefromItem,Customerwhere

Item.I_ID=Customer.I_ID.

(iv)ToincreasethePriceofallItemsby1000inthetableItem.

Ans:UpdateItemsetPrice=Price+1000

(v)SELECTDISTINCTCityFROMCustomer.

Ans:CityDelhi,Mumbai,Bangalore

(vi)SELECTItemName,MAX(Price),Count(*)FROMItemGROUPBYItemName;

Ans:ItemNameMax(Price)Count(*)PersonalComputer370003Laptop570002

(vii)SELECTCustomerName,ManufacturerFROMItem,CustomerWHEREItem.Item_Id=Customer.Item_Id;

Ans:CustomerNameManufacturerName

N.RoyPQR

H.SinghXYZR.Pandey COMPC.Sharma PQRK.AgarwalABC

(viii)SELECTItemName,Price*100FROMItemWHEREManufacturer=‘ABC’;

Ans:ItemNamePrice*100PersonalComputer3500000Laptop5500000

CHAPTER-15

DATABASETRANSACTIONS

SOLVEDQUESTIONS

1.Defineatransaction.

Ans.-Atransactionisalogicalunitofaworkthatmustsucceedorfailinitsentirely.Itisanatomicoperationwhichcanbedivideduntosmalleroperations.

2.Whatarethetwowaysinwhichmultipletransactionscanbeexecuted?

Ans.-Multipletransactionscanbeexecutedinoneofthefollowingtwoways:

(i)Serially(ii)Concurrently

3.What is asavepoint?

Ans.-Savepointsarespecialoperationsthatallowyoutodividetheworkofatransactionintodifferentsegments.Incaseofafailure,youcanexecuterollbackstothesavepointonly,leavingpriorchangesintact.

4.Whattoyouunderstandbyadatabasetransaction?

Ans.-Adatabasetransactionisalogicalunitofworkthatmustsucceedorfailinitsentirely.

5.WhydounderstandbytransactionCOMMITandROLLBACK?

Ans-COMMITingatransactionmeans all thesteps ofatransactionarecarriedoutsuccessfullyandalldatachangesaremadepermanentinthedatabase.TransactionROLLBACKmeanstransactionhasnotbeenfinishedcompletelyandhencealldatachangesmadebythetransactioninthedatabaseifany,areundoneandthedatabasereturnstothestateasitwasbeforethistransactionexecutionstarted.

6.WhatdoyouunderstandbyACIDpropertiesofdatabasetransaction?

Ans.-Toensurethedata-integrity,thedatabasesystemmaintainsthefollowingpropertiesoftransaction.ThepropertiesgivenbelowaretermedasACIDproperties-anacronymderivedfromthefirstletterofeachoftheproperties.

(i)Atomicity-This property ensures that either all operations of the transactions arereflectedproperlyinthe database, none are. Atomicity ensures either al-or-noneoperationsofatransactionarecarriedout.

(ii)Consistency-Thispropertyensuresthatdatabaseremainsinaconsistentstatebeforethestartoftransactionandafterthetransactionisover.

(iii)Isolation-Isolation ensures that executing transaction execution in isolation i.e. isunawareofothertransactionsexecutingconcurrentlyinthesystem.

(iv)Durability-Thisproperty ensuresthatafterthesuccessfulcompletionofatransactioni.

ewhenatransactionCOMMITs,thechangesmadebyittothedatabasepersisti.eremaininthedatabaseirrespectiveofotherfailures.

7.Whatthefunctionisofredoandundologs?

Ans.-Everydatabasehasasetofredologfiles.Itrecordsallchangeindataincludingbothcommittedanduncommittedchanges.Undologsstoredrollbackeddata.

8.WhatTCLcommandsaresupportedbySQL?

Ans.-SQLsupportsfollowingTCLcommands

•BEGIN|STARTTRANSACTION-Marksthebeginningofatransaction

•COMMIT-Endsthecurrenttransactionbysavingdatabasechangesandstartsanew

transaction.

•ROLLBACK-Endsthecurrenttransactionbydiscardingchangesandstartsanew

transaction.

•SAVEPOINT-Definesbreakpointsforthetransactionstoallowpartialrollbacks.

•SETAUTOCOMMIT-Enablesordisablethedefaultautocommitmode.

Q.WriteShortNoteson:e-Governance,e-Business,e-Learning.

Answer: e-Governanceinvolvesapplicationswhichareusedbygovernmentagencies/organizationstoprovidebettergovernance.

e-Businessapplicationsusetechnologytoeffectivelyaccessanddeliverbusinessrelatedservicesandperformvariouskindsofbusinesstransactions.

e-Learningapplicationsusetechnologytoeffectivelydeliverandmonitorlearningandteachingprocesses.Theyhelpthetrainertoorganizeandmanagehis/herlessonplans,presentthemtostudents/learners,evaluateandtakethefeedbacktoenhancefine-tunethisprocessinfuture.

Q.WhatareFront-end(Theuserinterface)andback-end(Thedatabase)?

Answer:AnITapplicationhastwomajorparts:Front-end(Theuserinterface)andback-end(Thedatabase).Thefront-endof anITapplicationis usuallyagroupofoneormoreformsthroughwhichtheuserenterstheinputvaluesandisshownthecorrespondingoutput.Agoodfront-endensurestheacceptanceoftheapplicationinthefirstgo.Theback-endofanITapplicationis thedatabaseinwhich all thedataisstored.Thisdatabaseresidesintheserver.Allthedatawhichisrequestedbythefront-endissuppliedbyback-end.Agoodback-endensuressustainability,efficiencyandeasymodificationoftheapplication.

Q.WhatarethetermsinvolvedinDevelopmentofanITapplication?

DevelopmentofanITapplicationinvolvescreationoffront-end,back-end,andconnectingthesetwo.Italsoinvolvestestingtheapplicationandthenimplementingit.

Q.WhatsocialandeconomicimpactsarefoundofICT.?

Answer:SocietyisimpactedasduetoICTpeoplechangetheirwayofconductingthetransactionsandthussavetheirtime,money,andenergy.Economyisimpactedas ICTleadstofastcompletionofdatatransferanddataprocessingjobs.ICTalsobringstransparencyintheadministration.

Q.WhatdoyoumeanbyInfomania?

Answer:Infomaniaistheconditionofreducedconcentrationcausedbycontinuallyresponding

toelectroniccommunicationssuchase-mail,SMSs,MMSsetc.ICTismakingmoreandmorepeopleinfomaniac.Thisismakingsomepeoplewastetheirproductivetimeintheoffice,neglecttheirfamiliesandduties.Somepeoplearealsoinahabitoffrequently checkingtheire-mailsevenwhentheyareonvacationwiththeirfamilies.WehavetobecarefulintheuseofICTsothatweuseitconstructivelyandnotgetobsessedwithitandbecomeinfomaniacs.

Q.WhatOSandfontsareusedforIndicLanguageSupport?

Answer:MacOS10.5supportsDevanagari,Gujarati,GurmukhiandTamil.Linuxbased

desktopssupportBengali,Devnagari,Gujarati,Kannada,Malayalam,Oriya,Tamil,TeluguandGurmukhi,

Q.WritethestepsforenablingIndicLanguageSupportinWindows.

Answer:Windows7andWindowsVistaincludeallthenecessaryfilestosupportIndic

languagesComplex(Indic)textsupportisautomaticallyenabled.ThereforeyoujustneedtoenablethekeyboardforthelanguagethatyouwanttousebyfollowingthestepsintheEnableakeyboardlayoutsection.ForWindowsXP,someadditionalsetupmayberequiredtosupportIndiclanguages.ThereforeyoufirstfollowthestepsgivenunderEnablingInternationalLanguageSupportinWindowsandthenproceedwiththestepsgivenundertheEnableakeyboardlayoutsection.

Q.Writethestepsforturningonthelanguagebar.

Ifyoudonotseethelanguagebarinthetaskbar(atthebottomofthedesktop)orfloatingonthedesktop

pleasedothefollowing:

Step1:ClickStart,clickControlPanel,andthendouble-click RegionalandLanguageOptions.Step2: OntheLanguagestab,underTextservices andinputlanguages, clickDetails asshownin

Figure8.

Step3: UnderPreferences,clickLanguageBar.

Step4: SelecttheShowtheLanguagebaronthedesktopcheckbox.

Figure3LanguageBarSettingsinWindowsXP

Note:YoucanswitchbetweendifferentlanguagesbyclickingonthelanguagebarandchangingthelanguageorbypressingtheleftALT+SHIFTkeys.

Q.HowFontsinWindowsareInstalled?

Step1: GotoWindowsFontsfoldere.g.C:\Windows\Fonts.(Thepathmay differonsome

computers.)

Step2:Copy-pastethefontfileintothisfolder.Windowswillnowinstallthefontfile.Step3: Onceinstalledthefontwillbeavailableinyourtext-basedapplications.

Q.HowcanbeestablishedFront-EndandDatabaseConnectivity?

AdatabaseapplicationconsistsofFront-EndandDatabase(Back-end).Thesetwoentitiescannotworkinisolation.Whateverdataisenteredbytheuserhastogotothedatabaseand whateverrelevantdataisextractedfromthedatabaseistobeshowntotheuserthroughtheFront-End.Therefore,theFront-EndandtheDatabaseofanIT applicationmustbeconnected.ThisconnectivityisachievedaslearntinChapter 6(DatabaseConnectivity).Iftheapplicationiswebbasedthentheconnectivityisachievedusingsomescriptinglanguage(likevbScriptorJavaScript).

Q.ArethereWebsitesinIndianlanguages?Writeaboutthem?

Answer:Yes,thesedaysmultipleGovernmentandprivateorganizationsareprovidingtheirwebsitesinHindiandotherregionallanguagesalso.Theaimistoprovidetheirserviceseventothecommon

peopleinremoteareas.Smalltownswherecomputersandinternethavereached,informationonthenetshouldalsobeavailableinregionallanguagessothatpeoplenotknowingEnglishcanalsohaveaccess totheinformation.Languageshouldnotbeahinderancebutasupporttolearning.Understaningtheimportanceofregionallanguages,manywebsiteshavealsoprovidedtranslationservicessothatthesamepagecanbeviewedinanylanguageofuser'schoice.