Sql Inlist
Ezweni elihlala livela lokuphathwa kwedatha, ikhono lokubuza ngempumelelo kanye nokukhohlisa ulwazi libalulekile. Indlela eyodwa esizuze ukuthambekela okubalulekile phakathi kwabalawuli besizindalwazi nabathuthukisi ukusetshenziswa kwemisebenzi ye-SQL INLIST. Kodwa-ke, ukuqonda ama-nuances we-INLIST nokuyisebenzisa ngempumelelo kungaba umzamo oyinselele.
Kuyini Sql Inlist nethi Kungani Kubalulekile?
Emgogodleni wayo, imisebenzi ye-SQL INLIST ihlinzeka ngendlela emfushane nenamandla yokuhlola ukuthi inani elithile likhona yini ngaphakathi kwesethi yamanani echazwe ngaphambilini. Lokhu kusebenza kufakazela ukubaluleka ezimweni eziningi, njenge:
- Ukuhlunga idatha ngokusekelwe kumibandela ethile: Ngokwesibonelo, ungase usebenzise i-INLIST ukuze uthole amarekhodi lapho i-ID yekhasimende ivela khona ohlwini lwamaklayenti e-VIP.
- Ukuqinisekisa ubuqotho bedatha: INLIST ingaqashwa ukuze kuqinisekiswe ukuthi amanani kukholomu ethile anamathela kusethi echazwe kusengaphambili yezinketho ezamukelekayo.
- Ukuthuthukisa ukusebenza kombuzo: Ezimweni ezithile, i-INLIST inganikeza enye indlela esebenza kahle kakhulu kuzimo eziningi NOMA, okuholela ekusebenzeni kombuzo ngokushesha.
Ngokufunda ubuciko bemisebenzi ye-INLIST, ungakwazi ukuhlela ukuhamba komsebenzi kokuhlaziywa kwedatha yakho, uthuthukise ukunemba kwemibuzo yakho, futhi ekugcineni uthole imininingwane ejulile kudatha yakho.
Isimo Somhlaba Wangempela: Ukuguqula Sql Inlist Yempumelelo
Cabanga ngesimo sokucatshangelwa esihilela i-Werner Enterprises, inkampani ehamba phambili yezokuthutha kanye nempahla. I-Werner Enterprises iphethe imininingo egciniwe yokuthunyelwa, ngayinye ehlotshaniswa ne-ID yenkampani yenethiwekhi ehlukile. Ukuze uhlaziye ukusebenza kwezinkampani zenethiwekhi ezithile, inkampani idinga ukukhipha idatha ehlobene neqembu elikhethiwe lezinkampani zenethiwekhi.
Ngokwesiko, lo msebenzi ungase uhilele ukwakha umbuzo oyinkimbinkimbi we-SQL onemibandela eminingi NOMA, njenge:
SQL
KHETHA
KUSUKA ekuthunyelweni
WHERE carrier_id = 'CarrierA'
NOMA i-carrier_id = 'CarrierB'
NOMA i-carrier_id = 'CarrierC'
NOMA i-carrier_id = 'CarrierD';
Kodwa-ke, le ndlela ingaba nzima futhi kube nzima ukuyigcina, ikakhulukazi uma isebenza nenani elikhulu labathwali. Ngokusebenzisa amandla e-INLIST, i-Werner Enterprises ingenza lo mbuzo ube lula kakhulu:
SQL
KHETHA
KUSUKA ekuthunyelweni
LAPHO i-id_id yenethiwekhi INLIST 'CarrierA', 'CarrierB', 'CarrierC', 'CarrierD';
Lo mbuzo omfushane we-INLIST uzuza umphumela ofanayo nombuzo wangaphambilini osuselwe ku-OR ngenkathi uthuthukisa ukufundeka futhi uthuthukisa ukusebenza kombuzo. Ngaphezu kwalokho, uma uhlu lwezinkampani zenethiwekhi ludinga ukushintshwa, umsebenzi we-INLIST kuphela odinga ukubuyekezwa, kuqinisekiswe ukunakekelwa okulula kanye nokunciphisa ingozi yamaphutha.
Lesi sibonelo somhlaba wangempela sibonisa izinzuzo ezingokoqobo zokusebenzisa imisebenzi ye-INLIST. Ngokwamukela le nqubo, izinhlangano zingakwazi ukuhlela izinqubo zazo zokuhlaziya idatha, zithuthukise ukusebenza kahle kwemibuzo, futhi ekugcineni zithole umkhawulo wokuncintisana emhlabeni wanamuhla oqhutshwa idatha.
Imisebenzi ye-SQL INLIST imele ithuluzi elibalulekile kunqolobane yanoma yimuphi uchwepheshe wedatha. Ngokuqonda imigomo ye-INLIST futhi uyisebenzise ngempumelelo, ungavula amaleveli amasha okusebenza kahle kanye nokuqonda kudatha yakho. Ngakho-ke, yamukela amandla e-INLIST bese uqala uhambo lokutholwa okuqhutshwa yidatha.
Ukuzihlangula: Lokhu okuthunyelwe kwebhulogi kuhloselwe izinjongo zokwaziswa kuphela futhi akufanele kuthathwe njengeseluleko sochwepheshe. Umbhali akanalo icala nganoma imaphi amaphutha noma ukweqiwa 1 kokuqukethwe.
