Database adapter
- 1. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 Database Database is a permanentlocationtostore ourapplicationdata.itholdsthe data intabularformat. ingeneral we will donormalizationtostore the data. what is normalization? decomposition of schemaintosubschemasiscallednormalization.innormalizationprimary and foreignkeyplaysmainrole. we make relationbetweenparentandchildtablesusingPrimary and ForeignKey's. PrimaryKey - thiswe use on parenttable field,itwon'tallow duplicatesandNULL valuestoinsert. ForeignKey - thiswe use in childtable field.itreferencestoparenttable. simple example inthe formof Tables.myparentTable isEmpand childtable idDept. Emp table No (Primary Key) First Name Last Name Sal 1 Abc Xyz 10000 2 Abc1 Xyz1 20000 3 Abc Xyz2 30000 inthe above table if we tryto insertthe same numberinthe "No" field,itraise primarykeyviolation exception. inthe above table if we tryto insert"NULL" inthe "No"field,israise "NULLvaluesnotallowed" exception. Dept Table NO (Primary Key) Name Type Emp No(ForeignKey ReferencesEmpTable "No" field) 1 A1 A1 1 2 B1 B1 1 3 A1 A1 2 4 A1 A1 3 one parentmay have 0 or manychild's.if we observe "EmpNo"fieldhasduplicate values. foreignkeyalwaysreferencestoprimarykey,withoutprimarykeythere isnoforeignkey. SQL ? it isa querylanguage todo CRUD operationsonTables.CRUDstandsfor Create,Read, Update and Delete. the followingare the querieswe use todoCRUD operations. Select*fromEMP - it fetchesall the recordsfromTable. Select*fromEMP where No=1 - itfetchesrecordsbasedoncondition,withthe "No"fieldvalues equalsto"1".
- 2. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 InsertintoEMP values() - itinsertsthe datain Table.like we have queriestoUpdate anddelete the recordsin table. Procedure in Database? isusedto execute multipleSQLstatementinasingle request.inprocedure we write multiple queries.if we execute the procedure,internallyitprocessall the queries. DB Adapter The purpose of DB adapterto execute SQLcommands andprocedures.Ingeneral we need to write some javacode to execute SQLcommands.Buton behalf Adapter doingthattask.Justwe needtoprovide some configurationlikeJNDIname of connectionpool andneedtoprovide SQL operationwhatwe wantto do. while workingonDBAdapterwe have to focuson followingsteps Creationof Data Source Configure DataSource inDB Adapter andUpdate DB Adapter UsingDB AdapterinApplication. Creationof Data Source we needtocreate Data Source inweblogicconsole.loginintoweblogicconsoleusing credentials(http://localhost:7001/console). clickon Service ->Data Sources -> New -> GenericData Source enterthe followingproperties Name : we shouldprovide the name,butitshouldbe yourchoice JNDINa me : we shouldprovide the name,butitshouldbe yourchoice,the followingisthe format we have to maintain,itisnot Mandatory,but itis a specificationwe shouldfollow. jdbc/name onyourchoice Note : if we provide name as"SOADataSource",itisgood to provide JNDIname as "jdbc/SOADataSource"
- 3. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 Database Type : Selectthe Database fromthe listandthenclick"Next" inthisscreenselectDatabase DriverandClickon Next.
- 4. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 we have two differenttypesof Database drivers,XA andnon-XA.thisi will explainlaterwhile explainingabouttransactionmanagement. inthisscreen,justClickon Next In thisscreenwe needtoprovide Database detailslike Database Name,HostName,Port,Database User Name,Password,andConfirmPasswordandthenClick onNext
- 5. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 the above detailsrelatedtomyDatabase. In thisscreenclickon"Test Configuration" - itvalidatesourconfiguration,if everythingwentwell it showssuccessmessage. inthisserverselectthe servertodeploy datasource and clickon finish Configure Data Source in DB Adapter and Update DB Adapter DB Adapter in Application DB adapter application in server Data Source Created in server
- 6. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 Whywe needto configure Data Source in DB Adapter? if we are usingDB adapterin our application,whenwe runourapplication,DBAdapterin our applicationcommunicatestoDBAdapteravailable inserver,DBAdapteravilable inserver communicatestodata source to getthe connection.usingthatconnectionwe cancommunicate to Database. followingare the stepstoconfigure DataSource in DB Adapter... Loginintoweb logicconsole ->Deployments Thenclickon DbAdapteravailable inlist
- 8. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 provide thenJNDIname andclickon "Finish",name ismandatory,butitshouldfollow the bellow specification,itisnotmandatoryto maintainlike this,butwe shouldfollow, eis/DB/some name eg:eis/DB/SOADataSource2 thenit navigatesthe followingscreen...thenextractthe javax.resource.cci.ConnectionFactory, we foundJNDIname whatwe createdinpreviousstep
- 9. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 thenclickon JNDIname,we will navigate tofollowingscreen, the defaultvalueinXA DataSource id empty,we shouldprovide the datasource JNDIname whatwe createdinfirststep. thenclickon "save". Once Againclickon deployments - > selectDbAdapterCheckBox ->Clickon"Update",itnavigates to followingpage.
- 10. vptaps@gmail.com @johnxavierv—twitter prathapkumarvemula@facebook.com http://www.slideshare.net/xavierjohn4 07775991224 selectthe option"Redeploythisapplicationusingthe followingdeploymentfiles",thenclickon "Next",innextScreenclickon"Finish". UsingDB Adapter in Application we needtodrag and drop intoexternal referenceorexposedservice area incomposite. while workingwithDBpollingoptionwe draganddrop inExposedservicesarea,inremaining scenarioswe place inexternal reference area. OpenJDeveloperIDEandcreate project (forcreatingprojectinJdeveloper,please followthe document" CreatingProject inJDeveloper.docx"),Draganddrop the Database Adapterfrom service Adapterslocation.