Ukubhala ezifundeni eziningi: kuphi lapho ushintsho luqinisekiswa khona ngempela?
Ukuhamba kwencwadi kuletha isicelo esifundeni; umngcele wokuthengiselana kuphela owenza ukubhala kube yinto eyodwa. Qamba into engaguquki, khetha umnikazi, bese udizayina ukuphinda uzame nxazonke zayo.
Amaseva amabili ezinhlelo ezifundeni ezimbili, iklayenti elilodwa elibhala nge-VPN, nombuzo ongabhalwanga muntu: yisiphi isigaba esinquma ukuthi ukubhala kwenzekile? Ukuhamba kwencwadi kuletha isicelo kunqubo. Umngcele wokuthengiselana unquma ukuthi ushintsho luba nini luhlala njalo futhi lubonakala. Le misebenzi ihlukene yenziwa izinhlelo ezihlukene, futhi igebe phakathi kwazo yilapho iningi lamaphutha okubhala ezifundeni eziningi lihlala khona.
Qala emthethweni webhizinisi, hhayi emephini
Qala ngomusho mayelana nomthetho webhizinisi hhayi ngezwe: yikuphi ukufunda nokubhala okufanele kuphumelele ndawonye, futhi yikuphi ukushintsha kwesikhathi esisodwa okufanele kube okungenakwenzeka ngesikhathi lokho kwenzeka. Ekubhukeni kwempahla lokho kusho ukuthi ukuhlolwa kwempahla nokubhuka kusebenza kokubili noma akukho neyodwa, futhi ayikho enye i-oda engasebenzisa leyo yunithi phakathi.
| Requirement | What satisfies it | What does not |
|---|---|---|
| All-or-nothing application | A transaction inside one owning system | A VPN path between regions |
| No double spend | Isolation strong enough to exclude the conflict | Atomicity alone |
| Survive a region loss | Replication the database itself documents | Two independent databases behind one client |
Yiwona mugqa ophakathi nendawo amaqembu awugxumayo. Ukuba yinto eyodwa ngaphandle kokuhlukanisa okwanele kwenza ukuthengiselana okubili kube ngakunye kuginisekiswe ngendlela efanele futhi kube nakho ukukhiqiza isimo ibhizinisi elisithatha njengokungenakwenzeka, futhi akukho kubuyisa emuva okuzolungisa lokho kamuva.
Umngcele owodwa onegunya unqoba amaseva amabili ezifunda
Amaseva ezinhlelo ezifunda angahlala lapho akhona, inqobo nje uma ethumela umsebenzi kunsevisi oyenza ngaphakathi komngcele owodwa wokuthengiselana osekelwe. Ungqimba lwezinhlelo luba umhleli womzila wenhloso; ungqimba lwemininingwane lunomqondo weqiniso.
Gcina lowo mngcele umfishane futhi useduze nemininingwane ewuthintayo. Ukuthengiselana okugcinwa kuvulekile ngesikhathi umuntu ephendula umbuzo, noma ngesikhathi ucingo luwela izifunda ezimbili, kuchitha isikhathi samalo sibambe izingidi futhi kwandisa ithuba lokuthi enye into iphelelwe isikhathi ngemuva kwaso. Lokho kwehluleka kubonakala njengenkinga yesizindalwazi kepha empeleni kuyinkinga yokuklama egqoke leso sikhwama. Ukuhambisa isinqumo ongqimbeni lwemininingwane ngokuvamile kuyisusa ngokuphelele.
BEGIN;
UPDATE inventory SET reserved = reserved + 1
WHERE sku = 'A-100' AND available >= 1;
INSERT INTO reservation (sku, order_id) VALUES ('A-100', 'ord-9f');
COMMIT;Funda lowo mfanekiso njengomngcele, hhayi njengesiphakamiso sokusebenza. Iphuzu ukuthi ukuhlola nokufaka kwabelana ngokuqinisekisa okukodwa, ngakho i-oda lesikhathi esisodwa liyabona impahla isetshenzisiwe noma aliyiboni nhlobo.
Isizindalwazi esikhophiwe sinikeza ini futhi asinikezi ini
Isizindalwazi esikhophiwe singanikeza umngcele obanzi lapho imodeli yaso yokuthengiselana isekela khona. I-Spanner ibhala ukuthengiselana kokufunda nokubhala okuyikho okukodwa ngaphakathi kwesizindalwazi esisodwa phakathi kwamatafula, ngokuhlukanisa okuchaziwe nokuziphatha kokuphinda kuzanywe. Leso yisiqinisekiso osifundayo, osivivinyayo futhi osethembayo ngamabomu.
Futhi yisiqinisekiso esivela kumkhiqizo, hhayi endleleni. I-VPN phakathi kwezifunda ishintsha indlela amaphakethe ahamba ngayo nendlela ukwehluleka okuvela ngayo. Ayandisi umngcele wokuthengiselana ngisho ngomugqa owodwa, noma ngabe umhubhe ubukeka uphilile kangakanani. Ukuhlanganisa lezi ezimbili kukhiqiza izakhiwo lapho yonke ingxenye idlula ukuhlolwa kwayo kepha imininingwane ayivumelani.
Izinzindalwazi ezimbili azibi wuhlelo olulodwa
Izinzindalwazi ezimbili eziphethwe ngokuzimela azitholi umphathi wokuthengiselana owabiwe ngenxa yokuthi amaklayenti angafinyelela kuzo zombili. Uma ibhizinisi lidinga ngempela isibophezelo esiyikho okukodwa kulolo mbhangqwana, indlela yokuxhumanisa, ababambiqhaza kanye nenqubo yokubuyisela konke kufanele kukhethwe futhi kugunyazwe esikhundleni sokucatshangwa.
Cabanga ngomzuzu lapho umbambiqhaza noma isixhumanisi sinyamalala ngemva kokulungiselela umsebenzi. Ukuqinisekisa okusabalele okusekelwe kungashiya isimo esingaqinisekile esidinga inqubo yokubuyisela nesinqumo sabantu, futhi akufiki nesithembiso sokuthi isifunda ngasinye sizohlala sikwazi ukubhala kukho konke ukuhlukaniswa.
Uma esikhundleni salokho ukuxhumanisa okungekho ngesikhathi esisodwa kwamukelekile, kusho lokho ngokucacile futhi ubhale izimo zebhizinisi eziphakathi kanye nemithetho yokubuyisana. Uchungechunge lwezinyathelo eziqinisekiswe endaweni enesinxephezelo luwukuklama okusemthethweni; akuwona nje ukuthengiselana okukodwa okuyikho ngaphansi kwelinye igama.
Dizayina ukuphinda uzame ngaphambi kokuphazamiseka kokuqala
Iklayenti lingalahlekelwa impendulo ngemva kokuba umsebenzi uqinisekisiwe, ngakho umshayeli akakwazi ukuthatha isikhathi sokuphela njengokwehluleka. Gcina ubunikazi besicelo obuhlala njalo futhi usebenzise umphumela wensevisi noma indlela yokungaphindi ngaphambi kokuphinda uzame ushintsho, ngaphandle kwalokho ukuphinda uzame kuba ukubhala kwesibili.
Izingcingo zokubuyisela zokuthengiselana ezizenzakalelayo zingasebenza ngaphezu kokukodwa ngemva kokukhanselwa okuphindayo, okukuzenza zibe yindawo embi yemiphumela yangaphandle engabuyiseleki. Gcina leyo ngaphandle kwengcingo yokubuyisela ngaphandle uma uhlelo lomsebenzi luchaza umthetho ophephile ocacile kuzo. Ukucophelela okufanayo kusebenza kukho konke okubiza imali noma okuthumela umlayezo. Ukukhokhiswa kabili kuyingxoxo enzima kakhulu kunomugqa welogi ophindwe kabili.
Ukumukelwa kufanele kudlale kabusha izimo ezine: amaklayenti amabili ancintisana ngomugqa ofanayo, ukukhanselwa inkonzo ethi kungaphindwa, ukuqinisekisa okungafiki neze impendulo yako, kanye nokulahleka kwesifunda noma isixhumanisi phakathi kwazo. Bhala umphumela webhizinisi oqinisekisiwe kanye nezimo ezingakaxazululwa eceleni kokuklama komzila, ukuze kimbe umuntu angaqondi iphutha ngokuthatha inethiwekhi njengengxenye enikeza isiqinisekiso.