I-Oracle SQL

I-Oracle Application Express, eyaziwa ngokuba yi-Oracle APEX, ifumene ukuthandwa okukhulu phakathi kwabaphuhlisi ngokusebenza kwayo okuphezulu kunye nojongano olusebenziseka lula. Isixhobo esomeleleyo sincedisa ekuphuhliseni izicelo zewebhu ezinzima ezixhaswa yi-Oracle database. Ngaphaya koko, yindawo enekhowudi ephantsi, eyenza abaphuhlisi abanamava amancinane benze izicelo.

I-Oracle APEX ibonelela ngeenguqulelo ezahlukeneyo, nganye izisa iimpawu ezongeziweyo kunye nezixhobo zenkqubo yophuhliso eyenziwe lula nesebenzayo. Ukuvela ngokukhawuleza kwe-Oracle APEX kunokwenza kube nzima ukulandelela umahluko phakathi kwezi nguqulelo.

Ngenxa yobunzima kunye nokuvela okuqhubekayo kwe-Oracle APEX, kuba yinto ebalulekileyo ukuqonda ukusebenza kweenguqulelo zayo ezahlukeneyo. Rhoqo, abaphuhlisi banokufuna ukubuza uguqulelo olwahlukileyo lwe-Oracle APEX esetyenziselwa ukulungiswa komsebenzi, ukusebenzisa iipetshi, okanye ukulungisa ingxaki.

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Xa usebenza ngoovimba beenkcukacha, umsebenzi oqhelekileyo kukulawula nokuhlalutya idatha ukuze ufumane ulwazi oluluncedo. Amaxesha amaninzi, oku kubandakanya ukujongana neentambo, ngakumbi ukuzohlula ngokusekwe kwimida ethile. Kwi-Oracle SQL, kukho iindlela ezahlukeneyo zokufezekisa oku ngemisebenzi eyahlukeneyo kunye neekhowudi zenkqubo. Kweli nqaku, siza kugubungela isisombululo esibanzi sokwahlula umtya usebenzisa i-Oracle SQL. Siza kuxubusha ingcamango, isisombululo, kwaye siphule ikhowudi ngesinyathelo ngesinyathelo ukuqonda okungcono.

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Ukudala ulandelelwano yinkalo ebalulekileyo ye-Oracle SQL. Ulandelelwano zizinto zesiseko sedatha apho abasebenzisi abaninzi banokuvelisa amanani apheleleyo. Kuyenzeka ukuchaza imiba ethile njengexabiso lokuqala ukuqala ngalo, ubungakanani bonyuso, kunye nowona mda uphezulu, phakathi kwezinye. Amanani aveliswa ngokulandelelana angasetyenziselwa iinjongo ezininzi ezifana nokuvelisa izifanisi ezizodwa, izitshixo eziphambili, amanani olawulo, kunye nezinye ezininzi.

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I-Oracle SQL lulwimi lwenkqubo olunamandla olusetyenziselwa ukulawula iinkqubo zolawulo lwesiseko sedatha (RDBMS). Namhlanje, siza kuphanda nzulu kwingcamango ethile - umyalelo we-SQL Drop Index.

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UkuLahla iSeti yoMgaqo yingqikelelo esisiseko kwi-Oracle SQL, esetyenziselwa ukuphatha, ukulawula, kunye nokulungelelanisa iiseti zedatha ngaphakathi kwendawo yedatha. Inceda ekugcineni imfezeko yesakhiwo solwazi lwesiseko sedatha ngokuchaza imithetho ethile eyalela ukuba idatha ingangeniswa njani, ithunyelwe ngaphandle, okanye icinywe. Kweli nqaku, siza kugocagoca ngokubaluleka kweSeti yoMgaqo wokuLahla, ukulandelelana kwezenzo ezifunekayo ukuyiphumeza, kunye nekhowudi ethile eyenza ukuba isebenze.

Kwi-Oracle SQL, Lahla iSeti yoMthetho yindlela esetyenziswayo ukususa umthetho omiselweyo kwisiseko sedatha. Isebenza kuzo zombini iziseko zedatha ezilula kunye nezintsonkothileyo, okwenza ukuguqulwa kwedatha kube lula. Iphucula ukusebenza kwesiseko sedatha ngokususa iiseti zemithetho ezingeyomfuneko okanye eziphelelwe lixesha kunye nokuphucula ukuphathwa kwedatha.

YEHLISA UMTHETHO SET rule_set_name;

Esi sisivakalisi esisisiseko soMmiselo woLahla. Umthetho_set_name ligama lomgaqo onqwenela ukuwuyeka.

Inyathelo ngenyathelo ikhowudi inkcazo

Ukwenza umsebenzi we-Drop Rule Set kulula kakhulu kwi-Oracle SQL. Yonke le nkqubo ibandakanya ukucacisa igama lomgaqo omiselweyo ukuba ucinywe kunye nomsebenzi ophezulu we "Drop Rule Set".

RHOXA UMTHETHO ISETHA imigaqo yomthengi;

Apha, umgaqo omiselweyo onikwe igama elithi 'customer_rules' uyayekwa.

Kubalulekile ukuqaphela ukuba ngaphambi kokuba umgaqo omiselweyo unokuchithwa, zonke izinto ezixhomekeke kuyo kufuneka zisuswe. Ukungaphumeleli ukwenza oko kuya kubangela impazamo. Emva kokuqinisekisa ukuba akukho zixhomekeke, ungaqhubeka nomsebenzi.

Amathala eencwadi aNxulumeneyo kunye neMisebenzi

I-Oracle SQL inikezela ngobuninzi bamathala eencwadi kunye nemisebenzi enokungena xa usebenzisa i-Drop Rule Set, njenge-DBMS_RULE iphakheji kunye nenkqubo ye-DELETE RULE SET.

Iphakheji ye-DBMS_RULE lithala leencwadi elinamandla elinoluhlu olubanzi lweempawu zokuguqula nokulawula iiseti zemithetho. Ibonelela abaphuhlisi ngeempawu eziluncedo zokulawula iiseti zemithetho, inceda ekusebenzeni kakuhle.

Inkqubo ye- DELETE RULE SET, kwelinye icala, ibandakanyeka kwinkqubo yokucinywa kweesethi zemigaqo. Yinkqubo engaphakathi ngaphakathi kwe-Oracle SQL esetyenziselwa ukwenza imisebenzi ye-Drop Rule Set.

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Kwihlabathi lenkqubo ye-Oracle SQL, enye yezinto eziphambili ekufuneka zijongwe, iquka ukugawulwa kweziganeko okanye imisebenzi yokuthuthuzela. Ikhonsoli yenza inxenye ebalulekileyo yokuhamba komsebenzi wokulungisa ingxaki, inika abaphuhlisi indlela yokulandelela ukusebenza kwenkqubo, kuquka nokuchonga iindawo apho imiba inokuthi yenzeke. Eli nqaku lingena kulo mba ubaluleke kakhulu.

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I-Oracle SQL isivumela ukuba sisebenzise kwaye silawule idatha kwiinkcukacha zolwazi. Imisebenzi eqhelekileyo ibandakanya ukubuza idatha, ukudala iitafile, kunye nokuphuhlisa iindlela zokucubungula idatha. Umsebenzi omnye rhoqo ophunyezwa ngabaphuhlisi ngeSQL kukukhetha imiqolo ethile kwitafile yedatha. Ngamanye amaxesha, kunokufuneka sinciphise ukuba mingaphi imiqolo esiyikhethayo, rhoqo ngenxa yezizathu zokusebenza. Ngokungagqibekanga, xa ubhala ingxelo ethi "KHETHA" kwi-Oracle SQL, ifumana yonke imiqolo kwitheyibhile echongiweyo ehlangabezana nemilinganiselo yakho. Kodwa kuthekani ukuba sifuna kuphela imiqolo eli-10 yokuqala? Kwesi sikhokelo, siza kubonisa indlela yokukhetha kuphela imiqolo eyi-10 yokuqala kwi-Oracle SQL.

KHETHA *
UKUSUKA (KHETHA *
UKUSUKA eyakho_itafile
UKUMISELWA ngomnye_umqolo)
PHI ROWNUM <= 10; [/ikhowudi]

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Ngokuqinisekileyo, makhe sithethe malunga nembono ye-Oracle SQL kunye neendlela zefashoni kunye nezimbo. Kodwa khumbula, ezi zihloko zahluke kakhulu, ngoko ke siza kuzisingatha ngokwahlukeneyo.

Imboniselo yegama leNkonzo ye-SQL ye-Oracle : Amagqabantshintshi

Imboniselo yegama lenkonzo ngumba obalulekileyo we-Oracle SQL. Ngokusisiseko, luphawu olunengqiqo lwesiseko sedatha, esisebenza njengesibizo somzekelo wesiseko sedatha se-Oracle eqhuba inkonzo ethile. Lo mbono wenza ukuba izicelo zokufowuna kunye nabasebenzisi badibanise kwaye basebenzisane nesiseko sedatha ngaphandle kwesidingo segama lomzekelo ocacileyo.

'Imboniselo yegama leNkonzo' inokusombulula iingxaki ezininzi, ezinjengokuvumela iinkonzo ezininzi ezahlukileyo ukujolisa kwisiseko sedatha enye okanye ukuququzelela ulungelelwaniso lomthwalo woqhagamshelwano kunye nokusilela.

YENZA OKANYE UTSHINTSHE BONISA_amagama_enkonzo AS
KHETHA igama, db_unique_name, network_name
UKUSUKA kwiinkonzo ze-v $;

Le khowudi ye-Oracle SQL yenza imboniselo yamagama enkonzo, apho umqolo ngamnye umele igama lenkonzo elivumela ukufikelela kwisiseko sedatha se-Oracle.

Igama leNkonzo lijonga njani umsebenzi kwi-Oracle SQL?

Inkqubo iqala ngokudala umbono. Lo myalelo we-Oracle SQL 'YENZA OKANYE UTSHINTSHE UMBONO' usetyenziswa ukwenza imboniselo entsha, okanye ukuba sele ikhona, ukuyibuyisela endaweni yayo.

Umyalelo KHETHA igama, db_unique_name, network_name FROM v$services; iqokelela onke amagama, amagama awodwa wedatha, kunye namagama womnatha asuka kwiinkonzo ze-v$-imboniselo eguquguqukayo yokusebenza ebonisa ulwazi kuzo zonke iinkonzo ezisebenzayo.

Emva kokuba imboniselo isekiwe, umntu unokuphonononga amagama enkonzo ngokuphumeza umgangatho KHETHA * FROM view_service_names; umbuzo. Isiphumo siya kuba luluhlu lwawo onke amagama enkonzo akhoyo anokusetyenziselwa iinjongo ezahlukeneyo.

KHETHA * KWI-view_service_names;

Izibonelelo kunye nokuSetyenziswa kweemeko zokuJonga igama leNkonzo

Enye yeenzuzo ezibalulekileyo zokusebenzisa amagama enkonzo kukwenza ulawulo olulula nolawulo lwe-Oracle database. Ngokomzekelo, inokunceda ekwalathiseni imithwalo yemisebenzi kwiimeko ezifanelekileyo zesiseko sedatha kwaye uqwalasele ulungelelwaniso lomthwalo wecala lomxhasi. Enye inzuzo kukuququzelela uqhagamshelo lwe-failover kwiindawo ze-Real Application Clusters (RAC).

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Ngokuqinisekileyo, sihamba!

I-Oracle SQL lulwimi olusebenza kakhulu olubonelela ngeqonga lokuphumeza imiyalelo ye-SQL ye-Oracle database. Isetyenziselwa ukulawula kunye nokukhohlisa izinto ze-schema ezifana nokudalwa kwedathabheyisi, ukuyilwa kwembono, ukudala ulandelelwano, ukudala izithethantonye, ​​kunye nezinye izinto ezintsonkothileyo. Kweli nqaku, siza kuxoxa ngomsebenzi onjalo osisiseko- ukongeza ikholamu kwitafile e-Oracle SQL.

ALTER TABLE table_name
YENGEZELA ikholamu_uhlobo lwekholamu_yegama;

Lo ngumyalelo osisiseko onokuwusebenzisa ukongeza umhlathi kwitafile esele ikhona. I-syntax ibandakanya umyalelo othi "ALTER TABLE" wokuguqula isakhiwo setafile, ubiza itafile onqwenela ukuyitshintsha, umyalelo "YENGEZELA" oxelela i-Oracle ukuba wongeza ikholamu entsha, kwaye ekugqibeleni igama lekholomu kunye nesibhengezo sohlobo lwekholamu. .

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