Ho beha Lethathamo ka Foromo ea Bobeli e Tloaelehileng
Nakong ea khoeli e fetileng, re shebile lintlha tse 'maloa tsa normalizing tafoleng ea data. Ntlha ea pele, re buile ka melao-motheo ea motheo oa basebetsi ba tloaelehileng. Nako ea ho qetela, re ile ra hlahloba litlhoko tsa mantlha tse behiloeng ke foromo ea pele e tloaelehileng (1NF). Joale, a re tsoeleng pele leeto la rona mme re koahele melao ea bobeli e tloaelehileng (2NF).
Hopola litlhoko tse akaretsang tsa 2NF:
- Tlosa li-subsets tsa data tse sebetsang melaong e mengata ea tafole 'me u li behe litafole tse fapaneng.
- Etsa likamano pakeng tsa litafole tsena tse ncha le ba pele ho tsona ka ho sebelisa lits'ebetsong tsa linaha tse ling.
Melao ena e ka kenyelletsoa ka polelo e bonolo: 2NF e leka ho fokotsa boitsebiso bo bongata ka tafole ka ho e nka, ho e beha tafoleng e ncha le ho theha likamano lipakeng tsa litafole.
A re boneng mohlala. Ak'u nahane ka lebenkele la inthanete le bolokang boitsebiso ba bareki boitsebiso. Ba ka 'na ba ba le tafole e le' ngoe e bitsoang Bareki ka lintlha tse latelang:
- CustNum
- Lebitso la pele
- Fane
- Aterese
- Motse
- Naha
- ZIP
Ho sheba ka bokhutšoanyane tafole ena ho senola boitsebiso bo fokolang ba data. Re boloka "Sea Cliff, NY 11579" le "Miami, FL 33157" ka makhetlo a mabeli ka 'ngoe. Hona joale, seo se ka 'na sa se ke sa bonahala haholo-sa eketsa polokelo mehlala ea rona e bonolo, empa nahana ka sebaka se senyehileng haeba re ne re e-na le mela e likete tafoleng ea rona. Ho phaella moo, haeba khoutu ea ZIP bakeng sa Sea Cliff e ne e lokela ho fetoha, re tla hloka ho etsa phetoho ena libakeng tse ngata ho pholletsa le database.
Ka mokhabo-taba o lumellanang le 2NF, tlhahisoleseding ena e fokolang e ntšoa mme e bolokoa tafoleng e fapaneng. Tafole ea rona e ncha (a re e bitsang ZIPs) e ka ba le masimo a latelang:
- ZIP
- Motse
- Naha
Haeba re batla ho ba matla haholo, re ka ba ra tlatsa tafole esale pele - poso ea ofisi e fana ka lengolo la mangolo a khoutu a li-ZIP hammoho le likamano tsa bona tsa metse / naha. Ka sebele, u kile ua thulana le boemo boo database ea mofuta ona e neng e sebelisoa. Motho e mong ea ntseng a e-na le taelo e ka 'na eaba o u kōpile hore a fumane code ea hau ea pele pele ebe o tseba motse oo le boemo boo u neng u bo bitsa ho bona. Ts'ebetso ena e fokotsa phoso ea basebelisi mme e eketsa katleho.
Hona joale kaha re tlohile dintlha tsa boipiletso ho tafole ea bareki, re khotsofetse molao oa pele oa foromo ea bobeli e tloaelehileng. Re ntse re hloka ho sebelisa senotlolo sa linaheng tse ling ho tlama litafole tse peli hammoho. Re tla sebelisa khoutu ea ZIP (sesebelisoa se ka sehloohong tafoleng ea ZIPs) ho theha kamano eo. Hona Basebelisi ba rona ba bacha ba bapala:
- CustNum
- Lebitso la pele
- Fane
- Aterese
- ZIP
Hona joale re fokotsa boleng ba boitsebiso bo bongata bo bolokiloeng boitsebisong ba rona 'me mohaho oa rona o le mokgwa oa bobeli o tloaelehileng!
Haeba u ka rata ho etsa bonnete ba hore setata sa hau sa motheo se tloaelehile, hlahloba lihlooho tse ling tsa rona lihloohong tsena:
- Litlhahiso tsa motheo tsa tloaelo
- Ho beha Letathamong la hau la Foromo ka Foromo ea Pele e Tloaelehileng
- Ho beha Letoto la hau la Boitsebiso ka Fomu ea Bobeli e Tloaelehileng
- Ho beha Letoto la hau la hau ka Fomu ea Boraro