Ajụjụ na-ejide ike nke nchekwa data gị
Ajuju nchekwa data na-ewepụta data sitere na nchekwa data ma debe ya na ụdị a pụrụ ịgbanwe. Ajuju a ghaghi ede ede n'asusu ndi choro choro choro-nke bu, asusu bu SQL .
Dịka ọmụmaatụ, mgbe ịchọrọ data sitere na nchekwa data, ị na-eji ajụjụ ị rịọ maka ozi akọwapụtara ịchọrọ. Ikekwe ị nwere teepu ọrụ, ma ịchọrọ ịgbaso ọnụ ọgụgụ ahịa. Ị nwere ike ịjụ nchekwa data gị maka onye ọrụ nke dekọtara ahịa kachasị elu n'oge a kara aka.
Nkọwa okwu SQL ahụ
Ajuju nchekwa data ga-agbaso usoro nyocha nke achọrọ site na nchekwa data. Ọdịdị kachasịsịsị bụ nsụgharị nyocha nke Structured Query Language (SQL) nke ọtụtụ usoro nchịkọta data jikwaa. SQL bụ asụsụ dị ike nke nwere ike ịjụ ajụjụ.
SQL na - eji nkwupụta SELECTION họrọ data kpọmkwem.
Tụlee ihe atụ nke dabeere na nchekwa Northwind nke na-ejikarị ngwa ahịa na ngwaahịa nchekwa data dị ka nkuzi.
Nke a bụ ihe edepụtara na tebụl ndị ọrụ na nchekwa data:
Onye ọrụ | Aha ikpeazụ | Aha mbụ | Aha | Adreesị | Obodo | Mpaghara | |
---|---|---|---|---|---|---|---|
1 | Davolio | Nancy | Onye nnọchi anya ịre ahịa | 507 - 20th Ave. E | Seattle | WA | |
2 | Fuller | Andrew |
| 908 W. Ụzọ Isi Obodo | Tacoma | WA | |
3 | Ịkọgharị | Janet | Onye nnọchi anya ịre ahịa | 722 Moss Bay Blvd. | Kirkland | WA |
Iji weghachite aha na onye ọrụ si na nchekwa data ahụ, nkwupụta SELECT ga - adị ka nke a:
Kpido aha mbụ, aha njirimara, edemede si n'aka ndị ọrụ;
Ọ ga-alaghachi:
Aha mbụ | Aha ikpeazụ | Aha |
---|---|---|
Nancy | Davolio | Onye nnọchi anya ịre ahịa |
Andrew | Fuller | Onye isi oche, Ahịa |
Janet | Ịkọgharị | Onye nnọchi anya ịre ahịa |
Iji nyochaa ihe ga-esi na ya pụta, ị nwere ike ịgbakwunye otu amaokwu ebe a:
Kpido aha mbụ, aha ikpeazụ si n'aka ndị ọrụ
EBE Ebe = 'Tacoma';
Ọ na-alaghachi aha mbụ na aha njirimara nke onye ọrụ ọ bụla nke sitere na Tacoma:
Aha mbụ | Aha ikpeazụ |
---|---|
Andrew | Fuller |
Rịba ama na SQL weghachite data n'ahịrị / kọlụm na-etolite yiri nke Microsoft Excel, na-eme ka ọ dị mfe ile ma rụọ ọrụ. Asụsụ ndị ọzọ nwere ike ịlọghachite data dịka eserese ma ọ bụ eserese.
Ike nke Ajụjụ
Ihe nchekwa data nwere ike igosi ụdị ihe dị iche iche na arụmọrụ, ma mana a na-ejikarị ya eme ihe site na iji ajụjụ ahụ. Ihe nchekwa data dị mgbagwoju anya nwere ọtụtụ tebụl na-echekwa ọtụtụ data. Ajuju na - enye gị ohere nyocha ya n'ime otu tebụl ka i wee nwee ike nyochaa ya nke ọma.
Ajụjụ nwere ike ime nyocha na data gị ma ọ bụ rụọ ọrụ ọrụ nlekọta data. I nwekwara ike nyochaa mmelite gị data tupu ịnye ha na nchekwa data.