The Structured Query Language (SQL) ndiyo inotevedzwa yemirayiridzo inoshandiswa kuwirirana ne database ye relational . Kutaura zvazviri, SQL ndiyo chete mutauro inonyanya kunzwisiswa. Chero pose paunosangana ne database yakadai, software inoshandura mirairo yako (ingave iyo inotsvaga mapepa kana zvinyorwa zvomufaira) muchitauriri cheSQL iyo database inonyatsoziva kududzira. SQL ine zvikamu zvitatu zvakakosha: Data Dhiyabhorosi Mutauro (DML), Data Definition Language (DDL), uye Data Control Language (DCL).
Shanduro Dzose dzeSQL paWebhu
Sekushandisa chero imwe yenhepfenyuro yepurogiramu yekombiyuta, unenge uchishandisa SQL, kunyange iwe usingachizivi. Semuenzaniso, webhuku rinotungamirirwa newebhu rekushandisa (sezvakaita mawebsite akawanda) rinotora mavoti ekushandisa kubva mafomu uye kuchitsvaga uye rinoshandisa iyo kunyora sQL mhinduro inowana mashoko kubva kune databata inoda kuunza peji yewebhu inotevera.
Chimbofunga muenzaniso wechinyorwa chekutsvaga paIndaneti zvine basa rokutsvaga. Peji yekutsvaga ingave ine fomu iri ine bhokisi rimwe chete raunoshandisa izwi rekutsvaga uye wovhara bhatani rekutsvaga. Kana iwe ukanyora bhodhi, server yewebhu inotora chero zvinyorwa kubva pane zvinyorwa zvemashoko ane nguva yekutsvaga uye inoshandisa zvigadziro kuumba peji yewebhu yakananga kune chikumbiro chako.
Semuenzaniso, kana iwe wakatsvaga mishonga ine izwi rokuti "Irish," sevha inogona kushandisa sarudzo inotevera yeSQL yekuwanazve zvinhu zvakabatana:
Dzakashandurwa, mutemo uyu unowana chero zvinyorwa kubva kune tafura yezvinyorwa zvinonzi "mishonga" ine mavara "asinganzwisisi" chero kupi zvako mukati mezita rekugadzirwa.
Data Dhiyabhorosi Mutauro
Iyo Dhiyabhorosi Dhimiro Mutauro (DML) ine chinyorwa cheSQL mirairo inoshandiswa kakawanda - iyo inongotora zvinyorwa zve database pane imwe nzira. Dzine idzi dzakawanda dzinowanikwa DML dzinorayira kuwana mashoko kubva pane dhesi ((SELECT) murairo, wedzera ruzivo rutsva kune database (mutemo INSERT), shandura ruzivo rwezvino rwakachengetwa mune databata (mutemo UPDATE), uye bvisa mashoko kubva kune database ( DONERA mutemo).
Data Definition Mutauro
Deta Definition Mutauro (DDL) ine mirairo isingawanzoshandiswa. DDL mirairo inoshandura shanduko chaiyo ye database, panzvimbo yezvinyorwa zviri mukati. Mienzaniso inowanzoshandiswa DDL mirairo inosanganisira iyo inoshandiswa kugadzira tafura itsva ye database (CREATE TABLE), shandura chimiro chetafura ye database (ALTER TABLE), uye bvisa tafura ye database (DROP TABLE).
Data Control Control Mutauro
Mutauro weData Control Control (DCL) unoshandiswa kugadzirisa kushandiswa kwevashandisi kune databases . Inoumbwa nemirairo miviri: mutemo we GRANT, wakashandiswa kuwedzera zvibvumirano zvemasvomhu kumunhu, uye murairo REVOKE, wakashandiswa kubvisa zvibvumirano zviripo. Iyi mirairo miviri inoumba nheyo yekodzero yekuchengetedzwa kwekuchengetedzwa kwemashoko.
Urongwa hweSQL Command
Nenzira yekuti isu isu tisiri mapurogiramu emakombiyuta, SQL mirairo yakagadzirirwa kuva neshoko rechikaka rakafanana neChirungu. Vanowanzotanga nemashoko ekuraira achitsanangura chiito chaunofanira kutora, chinoteverwa neshoko rinotsanangura chinangwa chemurairo (saiyo tafura chaiyo mukati me database yakagadziriswa nemurairo) uye pakupedzisira, zvikamu zvakatevedzana zvinopa mamwe mazano.
Kakawanda, kuverenga svoti yeSQL nekudanidzira kuchakupa pfungwa yakanaka kwazvo yekuti murairo unoda kuita. Tora kanguva kuverenga muenzaniso uyu weshoko reSQL:
Unogona here kufungidzira kuti chirevo ichi chichaitei? Inosvika patafura yemudzidzi we database uye inobvisa zvinyorwa zvevadzidzi vakapedza kudzidza muna 2014.
Kudzidza SQL Programming
Takatarisa zvishoma zvishoma SQL mienzaniso mutsamba ino, asi SQL iri mutauro wakakura uye une simba. Kuti uwedzere kujekesa, ona SQL Fundamentals .