53
1 Setup of PostgreSQL, pgAdmin and importing data CS3200 Database design (sp18 s2) https://course.ccs.neu.edu/cs3200sp18s2/ Version 2/9/2018
1
SetupofPostgreSQL,pgAdminandimportingdata
CS3200 Databasedesign(sp18 s2)https://course.ccs.neu.edu/cs3200sp18s2/Version2/9/2018
2
Overview
Thisdocumentcovers2issues:
1)HowtoinstallPostgreSQL:• PostgreSQLisapopularopensourcedatabaseserver.UnlikeSQLite,PostgreSQLisamuch
morefeaturerichdatabasemanagementsystem.WithPostgreSQL,youhave2components,theserverandtheclient.Thisisn'tverydifferentfromyourwebserver-browsermodelwherethebrowserisyourclient:ThewebserverservicesrequestsforfetchingwebpageswhereasadatabaseserverservicesSQLqueriesonadatabase.
• ThisdocumentwillguideyouthroughtheprocessofsettingupPostgreSQLonyourmachine.WhatthismeansisyouwillhavealocallyrunninginstanceofthePostgreSQLserveronyourmachine.
3
Overview• Justasawebbrowserhelpsmakerequeststoawebserveranddisplaystheresultsofthe
requestviz.awebpage,similarlyadatabaseclienthelpsyoufirequeriesatadatabaseserver(PostgreSQLinourcase),anddisplaystheresultsthatthedatabaseserversendsoverfromprocessingthosequeries.
• ThetwomostcommonclientsthatyouwillcomeacrosswhenusingPostgreSQLare"psql"whichisacommand-lineclientand"pgAdmin"whichisagraphicalclient.
2)HowtoimporttheIMDBdata:• DownloadthebigZIPfilefromouronlinedirectory.Itcontainsalargecollectionofdata
fromtheIMDBmoviewebsite.Thiswillcreateafoldernamedimdb2015,containing6.txtfiles.Youwillusethemtocreateadatabase.
4
1. Setup PostgreSQL (for MAC)
5
PostgreSQL
Goto:http://postgresapp.com/
• Gotohttp://postgresapp.com/.• Downloadthelatestreleasedversion(nottheprerelease!).
1)ClickHere toDownload
6
2)Extractthefileyoujustdownloaded.Typicallythedownloadedfileshouldbeinyourdownloadedfolder.
3)Thepreviousstepwillextractthe“Postgres”application,typicallyinthesamefolder.Lookforafilewithablueelephanticon.
4)DoubleclickonthisfileandPostgreSQLservershouldbeupandrunning.
7
5)WhilethePostgreSQLserverisupandrunning,youwillseeaniconshowupinyourmenubaratthetop.
6)Clickonthe“Slonik”inthemenubar.
7)Inthemenuthatshowsup,select“OpenPostgres”.
Iflateron,somethingisnotworking,verifythattheserverisrunning
8
9)Afteryou“OpenPostgres”,thiswindowprovidesyouwithallyourcreateddatabases.
10)Double-clickonthedatabaseyouwanttoworkwith.
9
11)Afterclickingonthedatabaseyouwanttoworkwith,thePostgrescommandpromptshouldopen,thatshouldlooklike<your_user_name>=#
12)Thisisthepsql clientthatwasmentionedearlierandwhereyouwillenterSQLcommandstointeractwiththedatabaseserver.
13)Tostoptheserver,simplyquittheapplicationbyclickingontheelephanticoninyourmenubarandselectingQuitfromthemenubarthatshowsupunderneaththeicon.
10
CommandlineCheatsheet
\l listexistingdatabases\c connecttoadatabase\d listtablesindatabase\q disconnectfrompsql
\d<tablename> viewdetailsofatablecreatedatabase<dbname> createDB
Alternatively,startfromterminalwithcommand"psql"
11
2. Setup PostgreSQL (for Windows)
12
• Goto http://www.postgresql.org/download/windows/.
1)Clickon“DownloadtheInstaller”
• Double click on the downloaded file. A window will show up that will guide you through the installation.
13
2)Doubleclickonthedownloadedfile.
14
3)AwindowwillshowupthatwillguideyouthroughthesetupofPostgreSQL.
4)Click“Next”tocontinuethesetup.
15
5)TheinstallerwizardwillaskyoutospecifyadirectorywherePostgreSQLshouldbeinstalled.Itisrightifyoustickwiththedefaultoption.Sojustclicknext.
6)Click“Next”tocontinuethesetup.
16
7)Theinstallerwizardwillthenaskyoutospecifyadatadirectory.Again,itisalrighttostickwiththedefaultoption.
8)Click“Next”tocontinuethesetup.
17
10)Click“Next”tocontinuethesetup.
9)Youwillnextbepromptedtoenterapasswordforthesuperuser “postgres”.EnterthepasswordandMAKEANOTEOFITasitwillberequiredeverytimeyouwanttoworkwithpostgres.
18
11)Youwillnextbeaskedtoenteraportnumberfortheservertolistenon.Thedefaultoptionshouldbe5432.Itisalrighttokeepitasitis.
12)Click“Next”tocontinuethesetup.
19
13)Next,leavethelocaleselectionat“Defaultlocale”
14)Click“Next”tocontinuethesetup.
20
15)Next,itwillaskyouifyouwanttoinstallStackBuilder.Youcanchecktheboxtoinstallit,howeveryoudon’tneedStackBuilderrightnowandpossiblynotforthedurationofthiscourse.So,youuncheckthebox.
14)Click“Finish”tocompletethesetup.
21
• Toopenpsql now(whichistheclientwewillusetocreateourdatabaseandinteractwiththedatabaseserver)gotothecommandpromptanddothefollowing:
17)Typethiscommand,asitis.
18)ItwillthenaskforthepasswordyousetduringthePostgreSQLsetup.Note:thatthepasswordyouenterwillnotbevisibletoyou,sojustkeeptypingitCORRECTLY!
19)Onexecutingthepreviouscommand,thepromptshouldchangeandshouldnowlooklike“postgres=#”
22
• Youarenowinthepsql programwhereyoucanenterqueriestointeractwiththePostgreSQLserver.
• Entering“\q”atthispromptshouldexitthepsql program.Example:postgres=#\q
23
3. Setup PostgreSQL (for Linux)
24
Step1:InstallPostgreSQL
HerearetheinstallationstepsonUbuntu(thisinstallationwillalsoworkonanyDebian-baseddistribution):1. Openaterminalwindow.2. Issuethecommandsudo apt-getsintall postgresql.3. Typethesudo passwordnecessarytogiveyouadminrightsandhitEnter.4. Allowapttopickupanynecessarydependencies.
Step2:Changethedefaultuserpassword
Ifyoudon’tfollowthisstep,youwillnotbeabletoadddatabasesandadministerPostgreSQL,andthedatabasewillnotbesecure.
25
• Here’showtochangethepasswordforthedefaultuser.Theuserinquestionispostgres,andthepasswordischangedlikeso:
1. Openaterminalwindow.2. Issuethecommandsudo passwd postgres.3. Type(andconfirm)thepasswordtobeusedforthisuser.
• Thepostgres userwillbetheonlyuseronyoursystemthatcanopenthePostgreSQLpromptwithoutdefiningadatabase,whichmeanspostgres istheonlyuserwhocanadministerPostgreSQL.
• Totestthis,changetothepostgres userwiththecommandsu - postgres andthenenterthecommandpsql.YoushouldnowbeatthePostgresprompt,whichlookslike:
postgres=#• Allotherusersgainaccesstothepromptlikeso:
psql DB_NAMEWhere,DB_NAMEisthenameofanexistingdatabase.
26
Step3:ChangethePostgresadminpassword
Theadministratorpasswordmustbeset;otherwise,externalapplicationswillnotbeabletocommunicatewiththedatabase.TochangetheadminpasswordforPostgres,followthesesteps:
1. Openaterminalwindow.2. Changetothepostgres user.3. Logintothepostgres prompt.4. Issuethecommand \passwordpostgres.5. Enter(andverify)thenewpassword.6. Exitthepromptwiththecommand \q.
27
Step4:Createyourfirstdatabase
Thisiswhereitgetsexciting.Let'screateanewdatabasecalledtestdb.Todothis,followthesesteps:
1. Openaterminalwindow.2. Changetothepostgres user.3. Logintothepostgres prompt.4. Issuethecommand CREATEDATABASEACTOR;.
28
4. Importing the data
29
1)Gotooursql directoryonourwebsiteandapagewithlotsoffileswillpop-up.
2)Downloadimdb-cs3200.zipandextractit.
30
3)Thiswillcreateafoldernamedimdb2015,containing6.txtfiles.
4)Now,inordertocreateadatabase,openPostgres,makesurethattheserverisrunningandconnecttopsql.
31
5)Oncetheserverisrunningandconnectedtopsql,youshouldseesomethinglike<your_user_name>=#asyourprompt.
6)Tocreateanewdatabase,enterthefollowingcommands:priyalmittal=#CREATEDATABASEimdb;priyalmittal=#\cimdb
Yourpromptwillthenswitchtoimdb=#
32
7)Youcannowusethefollowingcommandtocreateatable:imdb=#CREATETABLEtable_name(……);
YouwillhavetodecideontheappropriatedatatypesJ
8)Chooseappropriatetypesforeachcolumndspecifyallkeyconstraintsasdescribedhere.(partofyourfirsthomework)
33
9)Oncetablesarecreated,youcanusethepsql command\copy,toimportdatafromthecorrespondingtextfiles.
10)Thiscommandimportsdatafromthe“actor.txt”file,whichistobementionedalongwithitscompletepath,intotheACTORtable.
11)Thedelimiterspecifiesowthefieldsareseparated,whereasthelastpartofthestatementspecifiesthattheemptystringshouldbeassignedasaNULLvalue.
NOTE:The\copycommandmaytakeafewminutestocompleteforsometables(likelylongerthan10minforcasts).Theexactspeedoftheseoperationsmayvarydependingonyourmachine.
34
NOTE:Youmaygetanerrorwhenrunningthecopycommandthatlookssimilartothis:
ERROR:invalidbytesequenceforencoding"UTF8":0xc30x7c.
Thatmeansthatpsql issettoanencodingthatdoesnotmatchthefile.Trychangingtheencoding,andtrycopyingagain.
imdb=# set client_encoding to 'latin1';
35
5. Creating the .sql files
36
3)Pastethequeriesintoatexteditor,ASITIS,withoutmakinganychangestothefont,color,size,etc.andsavethefilewiththeextensionof.sql
2)Youmayaddcommentsintothefileasmentionedhere.
1)Copythequeriesyouwroteinthecommandpromptasitis,WITHOUTthe“imdb=#”.
37
PLEASENOTE:Addinganyextrasymbolsintoyour.sql file,suchas/ attheendofeachlineoranywhereelse,#,$,etc.mayresultintoerrorswhichwouldn’tletyourfilegetexecuted.Theonlyaddedtextpermittedisanylinethatispreceeded by"--":-- isusedtoaddcommentstothefile.
38
6. Environment Variables Setup
39
• Ifyouencountertheerror:“psql notrecognizedasaninternalorexternalcommand”issueforPostgreSql inWindows,thenyouaresupposedtofollowthesesteps:
2)Clickon“EnvironmentVariables”.
1)Whenyousearchyourmachinewith“Editthesystemenvironmentvariable”,thiswindowshowsup.
40
3)Double-clickonthehighlightedpath.
41
4)Clickon”New”andaddthehighlightedpathbelow.Ifyoufollowedthedefault,itshouldbethesame.Otherwise,youcancheckforthebin folderinthePostgreSQL folderandcopyitspath.
5)Clickon“OK”andrestartcommandprompt.Thisshouldhopefullysolvetheissue.
42
7. How to import an SQL file
43
• Youcanrunthechinooksql fileusingthefollowingcommandinpostgres prompt:
\i ‘319- Chinook– PostgreSql.sql’;
• \i filename.sql isthecommand.• Also,usethecompletepathofthefile
Example:
\i ‘/Users/……./foldername/319– Chinook– PostgreSql.sql’;
• YoucanalsojustcopyandpastethefileintoPgAdmin.
44
8. PgAdmin (version 3 or 4)
45
• pgAdmin isavisualclientforyourpostgres database• Youcaneitherusethelatestversion4ortheolderversion3• Noticethat– accordingtomanyusers– version4ismorecumbersomethanversion3.Wethusrecommendthatyoudownloadversion3insteadofversion4:https://www.pgadmin.org/download/
• Youmaygetsomeerrorswhenfirstinstallingwhenworkingwithpostgres 10,buttheyshouldnotpreventyoufromusingit
46
ConnectingtoPostgreSQLdatabasewithpgAdmin 3(afterpgAdmin 3issuccessfullyinstalled)
1)OpenPostgres,suchthattheslonik iconshouldappearonthetopofyourdesktop.
2)Doubleclickontheparticulardatabase,forwhomtheconnectionwithpgAdmin 3istobeestablished,toopenitscommandprompt.
47
3)Afterclickingonthedatabase,itscorrespondingcommandpromptshouldopenup.
4)WritethisstatementasitiswiththePASSWORDofyourchoice.
NOTE:(i)Please,notethepasswordsomewhereasyouwillneedtoenteritintopgAdmin,everytimeyouwanttorunqueriesforadatabase.
(ii)REMEMBERTOADDTHESEMI-COLON.
48
Now,tosetupanewserveconnectioninpgAdmin,openpgAdmin and:
5)GotoFile->AddServer
6)EnsurethattheNameandHostissettolocalhostandthePortto5432(unlessyouhaveconfigurePostgreSQLforadifferentport)
7)EnterthePasswordyoujustsetforthedatabaseinthePostgrescommandprompt.
RESTALLREMAINSTHESAME!
49
Toconnecttotheserver: 8)Double-clickontheserveritem.
9)Providethepasswordwhenprompted.Youprobablywanttostoreit
50
10)ClickOKeverytimeyougetapop-up.YouwillhavetoclickOKseveraltimes.
51
11)TochecktheTablesintheDatabase,expandtheparticularDatabase.
12)ExpandtheTablestocheckwhatalltablesarepresentinthedatabase.
RightclickonDatabasesinordertocreateandaddanewdatabase
52
13)ToopentheSQLwindowtorunqueriesoveraparticulardatabase,clickonthedatabase.
14)ThenclickonthisSQLbutton.
53
15)Thisiswhereyoucanrunqueriesforaparticulardatabase.
ThisindicatestheDATABASEthatyouarecurrentlyworkingon.
Afterwritingaquery,pressthisRUNbuttontoexecutethequery.OrjusthitF5
