Functional nedoro uye ndeyeukama Databases

Information yagara iri zvakakwana simba mhindu. Development, ndeyeukama Databases uye ruzivo rwokugadzira zvinhu zvirongwa mitauro Akakurumidza kuchinja kugutsikana uye maumbirwo mubereko. Pane imwe yakaoma kumiririrwa hurongwa. Formalization, chaiyo masvomhu uye binary ukama vave inobudirira uye kukura nokukurumidza, nzvimbo unyanzvi uye ruzivo.

Zvakasikwa mashoko haasati achinja emuchina ayo uye kuwedzera kugutsikana uye mamiriro, akakwira pakakwirira itsva. It ane mvere chimiro, uye zvakasikwa hapana "rectangular". Information Chokwadi, anofanira formalized, asi ine simba, kuchinja kwete chete mashoko uye algorithms pamusoro kubudiswa dzavo, kuchinja mabasa pachavo uye minda yavo kushanda.

Information> formalization kuti mashoko >>

Mashoko ari dzikwanise humboo (date womuenzaniso, mashoko mamiriro, mashoko nechigadziko ...) sezvo anoona programmer. Hazvivimbisi kuti chiratidzo ichi zvakarurama, asi kana chirongwa anopedza dambudziko, humboo akabva vakaisawo zvakakwana napo.

Mubvunzo sei zvakakodzera formalized mashoko - nyaya nguva. Kusvikira zvino, pfungwa rinomutsa (kuzviremekedza kuchinjira kumamiriro Zvichidiwa kushandiswa) - chete hope mapurogiramu.

Functional nedoro: "chisarudzo chakarurama = chirongwa (programmer)" uye mamiriro "dambudziko kuramba kutevedzera" zvinokosha kazhinji, asi chete pamwe chete. Asi ichi hachisi kwemasvomhu hwaro, iyo inoshandiswa kusika Databases.

Direct okuti: dzinongoitika uye kuramba emuchina mashoko uye matambudziko algorithms chaizvo nguva dzose. A ndeyeukama Database chinhu binary yomumba + + muchinyatsochenjerera masvomhu yakarurama yakarongwa kugadzira + ...

Data, mafaira uye Databases

How date inochengeterwa refu hazvina basa nguva, kungava ndangariro kana ane mudziyo kwokunze. chinoumba Hardware kwasvika vachiwana kumhanya okukura uye nechokwadi unhu hwakanaka bhuku guru.

Main okuchengetera zvokusarudza, akasiyana embodiments pakushandisa:

• mafaira;
• Database.

Chokutanga anopiwa panguva ngoni programmer (kuti zvinyorwa, muna pamanyorerwo chii, sei kuzviita, kuverenga ...), wechipiri pakarepo kunounza kudiwa zivo nyore dzichipfekeka dependencies.

The zvakabudiswa zvazvingava uye kunyora mashoko mafaira (mafungiro kukura uye kwete muchadenga) ndiko kutsanya chaizvo, uye dzimwe nguva kumhanya Database remapazi zvakafanana kunogona yekudyidzana nomumugwagwa kwaitora nguva.

Personal ruzivo uye seboka uchenjeri

Munhau kwave kuedza kuenda mhiri muganhu zvasvika, asi nhasi rinorwisana ndeyeukama Databases. A fuma yokungotaura mukana, muitiro zvikuru uye Developers - vanokwanisa.

Pfungwa dzichipfekeka nedoro kuti Database Developers kumanikidza programmer, kunyange kana iye haana kuronga kushandisa upfumi akarongeka-musoro ruzivo yokuvaka kunzwisisa mashoko zvivako, pezvakaitwa, basa navo, zvakabudiswa uye kunyora ruzivo.

Kunyange zvisiri zvazvingava, programmer kunobva Database pfungwa, pasinei anosarudza kushanda. Hapana chido kutevera canons, unogona kushandisa mafaira kuti awane yakawanda mafaira, uye mujenya pauzima. yakawanda pachako nguva richaperera, uye dambudziko zvichapedzwa kwenguva refu.

Hazvinei yakaoma sei kuonekwe mienzaniso dzichipfekeka nedoro, hazvirevi hazvo kunyura munzvimbo dzakadzika zvinoreva uye zvisingarambiki. Kazhinji, zvinofanira kuzivikanwa kuti seboka uchenjeri kukwanisa kusika Databases siyana, akasiyana kukura uye functionality:

• chikukutu Oracle;
• kuda kuti MS ari SQL Server ;
• nevakawanda MySQL.

- kwazvo ndeyeukama Databases vane mukurumbira wakanaka, nyore kushandisa, kutsanya mumaoko unyanzvi. Kushandiswa yavo anoponesa nguva uye hakubvisi kudiwa kunyora inotevera jira webetsero romutemo.

Features Programming uye Data

In mapurogiramu vagara chirwere kunoramba rewritten, kudzokorora basa vamutangira, kuti zvimwe chinhu kuti ajairane achinja mashoko, basa, kana kuti mamiriro ezvinhu kushandiswa kwayo.

The peculiarity of dzichipfekeka nedoro kuti, sezvo ari zvirongwa kukanganisa kunogona kudhura chaizvo. The basa iri kazhinji nyore. Kazhinji, munguva formalization mashoko yaunganidzwa zvakaoma cherudo mashoko. zvinhu zvavo kazhinji vanozivikanwa, ipapo vari chokuita nedzimwe ukama anokosha, ipapo ari yakasimbiswa algorithms chimiro matafura, queries, mashoko acho algorithms.

Kazhinji kukosha kukuru akasungirirwa yeEncoding. Havasi Databases zvose kupa Mobile zvingaitwa kazhinji nezvisarudzo sei zvakanaka zvirire MySQL, iro riri gumi nevaviri Databases, wakanakisisa uye akatsiga kushanda, kumanikidza yokuvaka kuti regumi pangoro akafanana avo vatovako.

Pane nguva apo munhu vaiita Hosting ichikutadzisa ari functionality pamusoro PHP uye zvinokanganisawo zvirongwa zviri Database kuwana.

Mazuva ano zvirongwa mutoro vakaenzana basa chirongwa algorithm kuti nokuumba date muenzaniso. All vanofanira kushanda, asi iwe unofanira nguva dzose vanoshamba kupinda inovhiringidza yokuchinja dzidziso.

Db: nyore ukama ari mashoko

Chokutanga, pfungwa Database - Database ichi sezvo ane utariri gadziriro Databases (semuenzaniso, MySQL), uye mamwe mashoko mamiriro tichiratidza date zvinhu uye ukama pakati pavo. Mumwe Database MySQL «vabatisise» pachayo sezvo vakawanda mashoko hurongwa kuti mafomu siyana. Imwe Oracle Database anogona kupa ruzivo pezvakaitwa imwe kambani hombe kana kubhengi kudzora kuchengeteka uye umboo kuvimbika panguva soro yakati sandara, vari riri pamusoro yakatarwa makombiyuta vari dzakasiyana marefu akasiyana turusi runyararo.

Akagamuchira zvokufungidzira kuti reshiyo nderei ndeyeukama womuenzaniso. An chepuraimari ukama - ndiko chine mbiru uye mitsara mazita tsika. Classic "bhokisi" (ona tafura) - iri nyore uye inobudirira mberi. Kunzwisisa uye dzichipfekeka kutsamira pamusoro Database kunotanga apo "mabhokisi" vari kutanga kupinda noukama nomumwe.

Zita rimwe mbiru imwe tafura anofanira kuva nemamwe ari akapoteredza dambudziko. The chete havagoni kupiwa pamahwandefa maviri. Ziva zvinoreva pfungwa:

• "Chinonzi musimboti";
• "Siya redundancy";
• "Ukama Fixed";
• "Kuitira kururama."

- mumwe zvokutanga vanofanira kushandisa Database uye kuvaka date muenzaniso basa chairo.

Kutyora chipi idzi pfungwa - rakadzika kunyatsoshanda ari algorithm, anonoke mashoko zvakabudiswa, mashoko kurasikirwa nezvimwe zvinetso.

Functional nedoro: nomusoro uye zvinoreva

Haukwanisi kuverenga pamusoro tuples ukama, nezvokuti mashandiro - chine nharo chienderane tsika uye mashandiro - haisi nzira yemaitiro kana purogiramu, asi zvinogona kupiwa tsika - tafura.

Kwete hazvo, asi haina kukuvara kumiririra dzichipfekeka ukama se:

F (x1, x2, ..., xN) = (y1, Y2, ..., Yn).

Asi iva nechokwadi kunzwisisa kuti pamusuo - netafura, goho ndiyewo tafura kana imwe sarudzo. Kazhinji, ari kushanda ukama anogadza pfungwa neukama pakati matafura, queries, ropafadzo, ude, zvakachengetwa maitirwo ezvinhu zvimwe nguva (zvinoriumba) Database.

Kazhinji, tafura vari dzikwanise mumwe, akazozviratidza kune mugumisiro. Asi kushandisa dzichipfekeka nedoro haringorevi pfungwa yakadaro. The programmer anovaka cherudo mufananidzo data, umambo wokuenzanisira, mashoko mamiriro ... pasinei kumutumidza, asi kana anoshandira imwe Database, inofanira kuvakirwa ayo pfungwa, kufunga zvarinoreva uye remutauro mutauro kushandiswa, sezvo mutemo, SQL.

Zvinogona vakati dzichipfekeka ehupfumi ari Database dependencies anowanika kuburikidza bazi remutauro aishandiswa mutauro SQL. Asi zvikuru kukosha kunzwisisa kuti pashure zvose nemateru makata kukura, kwete Databases zhinji kudaro akapona, asi tumitauro vazhinji mutauro uye chaizvo yomunyika hurongwa vari Databases, zvakare.

Oh zvakanaka Excel yekare

Kana kombiyuta akaratidza zvinobatsira divi, nyika iri kamwe rakakamurwa programmers uye vanoshandisa. Kazhinji, kushandisa rokutanga:

• PHP, Perl, JavaScript, C ++, Delphi.
• MySQL, Oracle, MS SQL Server, Visual FoxPro.

wechipiri:

• Shoko.
• Excel.

Vamwe vanoshandisa vanokwanisa kuita zvavanoda (pasina kubatsirwa programmers) muShoko Database - munhu maturo chaiyo.

Zvakaitika vanoshandisa muna Excel kusika munhu Database - hunoshanda uye hunakidze. Chinhu chinokosha ndechokuti Excel, roga, ndiyo yaishandiswa, mavara uye anobatsira.

Tabular pfungwa akaita kunotsanangurwa pfungwa dzichipfekeka nedoro kuti maonero uye Accessibility, asi nuances vari mumwe Database. Munhu wose ane pachake "chiso" zvavo, asi kubva Excel kuna Oracle konzera nyore dzinoungana, kureva pamatafura.

Kana isu funga kuti Excel - ichi hachisi Database, asi vazhinji, vanoshandisa (kwete Developers) rinoshandiswa saizvozvo, uye Oracle - yakaoma uye simba kuti vabudirire chikwata chikuru Developers riri mumunda Databases, zvinovawo nyore kubvuma - the Database ndiwo mufananidzo kunyanya programmer (chikwata) maduramazwi dambudziko uye ayo mhinduro.

Chii ukama chadzo, pamwe chii, apo, nei ... sokuti chete kune munyori kana boka rayo.

About apo ndeyeukama mafungiro vari

Scientific uye kwesayenzi mberi - chinorwadza kwazvo nzira, uye dzimwe nguva utsinye. Kana unoyeuka apo Database vakatanga, izvo * .dbf, vose vakapiswa cybernetics, ipapo kudanana kombiyuta nesayenzi uye akatanga kuronga vhiringidza kufamba yepamusorosoro panguva nyika yakati sandara, zvinova pachena nei ndeyeukama Databases vari saka akaoma musoro uye dzakanaka. Nei chaiwo manyorerwo nhasi mhenyu zvirongwa, uye chinhu vaifarira zvirongwa zviri nyore kukosheswa, asi haisati kutongwa.

Hazvinei akanaka ari dzichipfekeka ukama mumaratidzirwo wemasvomhu sei:

Iyi haisi ukama binary, kana panzvimbo, ndiko mukana uongorore zvakare pfungwa pave noukama pakati muzvizhinji unhu, kuongorora "mumwe-to-zhinji" muchikurukurirana, "vazhinji mumwe", "vazhinji zhinji" kana "vazhinji kuita, uye pane imwe."

Options ukama vanogona kubuda zvakawanda. Izvi wemasvomhu kuti pfungwa, uye kuomesa! Information - ane pachake masvomhu ayo, inokosha. Zvinogona chete kuva chokungoendawo kutaura pamwe kuvamirira kwazvo.

Unogona formalize basa vashandi dhipatimendi, nyora ACS nokuda dzokubudisa mafuta kana kugadzirwa mukaka, chingwa, kuita kusarudzwa nenzira huru mujinga Google, Yandex uye Rambler, asi mugumisiro kucharamba kunofambira mberi, uye pfungwa imwe neimwe nguva ndiyo chete!

Kana dzichipfekeka ukama = zvachose pfungwa uye masvomhu = panobva Database, vorudzii emuchina tinogona kutaura. Chisarudzo chipi achava wevakadzidza, chero pamutemo mashoko muenzaniso + = zvakaoma algorithm chaiwo uye wakajeka chisarudzo. Information uye yezvinoreva chero chirongwa anoshandura nguva dzose.

Mharidzo kutsvaka injini pamusoro chete kutsvaka mashoko haagoni kuva zvakafanana pashure kweawa kana mbiri, uye, zvakajeka, muzuva - kana kutsvaga acho anoreva mashoko nharaunda umo nhamba nzvimbo, zvinhu, ruzivo, uye zvimwe zvinhu zviri mberi kuchinja .

About nemitsetse uye zvinhu

Kunyange kana chirongwa chinokuvadzwa akarongeka, uye ayo Database kunyange kufunga pamusoro simba vose tiine mutsetse. Uye pane nguva mutsetse. Uye magumo hazvigoneki. Zvingasava kunyange kuva shanduka, kuti shanduka chete conditionally. Uyezve, chero Database wavo akarongeka uye binary-muboka revatungamiriri zvinoisa hwakawanda chokungoitawo, uye ichi nokukurumidza + unhu zvakabudiswa uye Uropi.

строки условно-переменной длины с массой бинарных формальностей и строгих математических ограничений. Kana minda izvi kana zvimwe ari Database pakati data, kunyanya chaiye ari kukamurwa zvichawedzerwa: Judhasi nhamba, pamberi tsamba 'e', mharidzo youduku - mune pfupi kwose kwose uye nguva dzose zvinokosha ehupfumi pakati dzichipfekeka Database dependencies: tambo zvimiso shanduka kureba ane guru binary chokungoitawo uye kuzviomesera kwemasvomhu constraints.

Kana kushandura inzwi uye kuteerera kupomba pakati rinomutsa, zvose zvinhu zvinogona nechepadivi. In wokutanga rakada, mbiru zita iri tafura - chiri chinhu, mazita mazita - zvakafanana chinhu, mune tafura pfupi - chinhu chimwe Header uye mazita mbiru iri Header. Uye nguwani vasingagoni kuva ...

Zvisinei, hungiso kungava tafura. Uye mumutsara kunogona kuva kunokosha. Uye nei nguva dzose vave nhamba iyoyo. Full sikweya tafura - ichi Kunyanya, uye kakawanda, pasiri paruzhinji.

Kana kufungidzira mazano ose ari Database zvinhu, zvino, zvichida, hazvidi kuvaka yakaoma binary pabonde. Uyu dzinongoitika uye pfungwa chaiyo, kana chete nokuti ane chinangwa (kwete kwemasvomhu) pfungwa inoratidza simba mashoko uye zvakatipoteredza umo mune mabasa.