Cov Tswv Yim Kom Ua Hauj Lwm Nrog Cov Databases Yooj yim
Cov ntaub ntawv ua ke nyob rau hauv ib hom kev tuaj yeem suav tau tias yog ib qho chaw khaws ntaub ntawv. Muaj ntau daim ntawv sau npe siv rau cov databases thiab lawv siv nyob rau hauv txhua qhov kev zov me nyuam thiab cov kev pab cuam uas khw muag khoom lossis rov qab tau cov ntaub ntawv.
Yog tias koj tab tom pib nrog databases, hauv qab no yog qhov teeb meem ntawm cov khoom saum toj kawg nkaus uas koj yuav tsum paub ua ntej tsiv rau pem hauv ntej. Cov lus tseeb no tau lees tias yuav ua kom yooj yim rau kev ua hauj lwm nrog databases thiab ua kom muaj kev tsim tau.
01 ntawm 05
SQL Cov Ntawv Core of Dational Databases
Koj tsis tuaj yeem tsis muaj nws: Cov Lus Cog Tseg Lus ua rau cov tub ntxhais ntawm txhua yam kev sib txuas lus. Nws muab ib qho interface rau Oracle, SQL neeg rau zaub mov, Microsoft Access, thiab lwm yam kev sib txuas lus databases, thiab yog ib qho "yuav tsum kawm" rau tag nrho cov neeg siv kev kawm database.
Nqa ib qho introductory SQL kawm ua ntej koj txawm sim mus kawm tej database software. Lub sij hawm peev yuav pab koj tsim ib lub hauv paus zoo thiab pib ntawm txoj kev taw qhia hauv lub ntiaj teb ntawm databases.
W3Schools.com yog qhov chaw pib zoo rau cov neeg nyiam tshiab hauv SQL. Ntau ยป
02 ntawm 05
Xaiv lub Koom Haum Me Nyuam Yaus yog qhov txiav txim siab tseem ceeb heev
Kev xaiv ntawm tus thawj qhov tseem ceeb yog ib qho kev txiav txim siab tseem ceeb tshaj plaws uas koj tau ua nyob rau hauv tus txheej txheem ntawm cov ntaub ntawv tshiab. Qhov tseem ceeb tshaj plaws yog tias koj yuav tsum xyuas kom meej tias qhov tseem ceeb tau xaiv yog qhov tshwj xeeb.
Yog tias nws muaj peev xwm hais tias ob qho ntaub ntawv (yav dhau los, tam sim no, los sis yav tom ntej) yuav sib qhia tau tus nqi qub rau tus cwj pwm, nws yog qhov kev xaiv tsis zoo rau thawj qhov tseem ceeb. Thaum ntsuas qhov kev txwv no, koj yuav tsum xav txog creatively.
Koj yuav tsum tsis txhob cuam tshuam txog qhov tseem ceeb ntawm kev txhawj xeeb, xws li Social Security Numbers.
Yog xav paub ntxiv txog kev xaiv ib qho tseem ceeb thawj qhov tseem ceeb, saib Xaiv Lub Koom Haum Me Nyuam Yaus .
03 ntawm 05
NIAM TSIS XOOM ZAUM lossis DABNEEG
NULL yog ib qho tseem ceeb heev nyob rau hauv lub ntiaj teb ntawm databases, tab sis nws yog ib yam uas pib tshiab feem xyuam.
Thaum koj pom tus nqi NULL, txhais tau tias nws yog "tsis paub." Yog hais tias muaj ntau yog NULL, uas tsis tas txhais tias nws yog xoom. Zoo sib xws, yog hais tias cov lus teb tuav cov nqi lus , nws tsis txhais hais tias tsis muaj qhov tsim nyog - nws tsis paub meej.
Piv txwv, xav txog lub database uas muaj cov ncauj lus qhia txog cov menyuam uas tuaj koom lub tsev kawm ntawv. Yog hais tias tus neeg nkag hauv cov ntaub ntawv tsis paub tus tub kawm ntawv lub hnub nyoog, tus nqi NULL siv los qhia tias "tus neeg tsis paub". Tus tub kawm ntawv yeej muaj hnub nyoog - nws tsis yog tam sim no nyob rau hauv cov ntaub ntawv.
04 ntawm 05
Hloov Spreadsheets rau Databases Saves Time
Yog hais tias koj twb muaj tons ntawm cov ntaub ntawv khaws cia hauv Microsoft Excel los yog lwm cov ntaub ntawv spreadsheet, koj tuaj yeem txuag koj tus kheej cov roob hauv lub sijhawm los ntawm kev hloov cov ntaub ntawv spreadsheets rau hauv cov ntaub ntawv database.
Nyeem peb cov ntaub ntawv ntawm Hloov Excel Spreadsheets mus Access Databases kom pib.
05 ntawm 05
Tag nrho Database Platforms YUAV TSIS TAU LI CAS
Muaj ntau ntau yam databases tawm muaj, tag nrho cov neeg uas muaj ntau yam ntawm nws tus kheej ntawm cov nqi sib txawv.
Qee cov muaj npe-txheej txheem databases uas tsim los rau cov lag luam loj lossis loj cov ntaub ntawv pabcuam rau cov lagluam. Lwm tus yog cov duab databases zoo tsim nyog mus nrhiav khoom muag rau ib lub khw me me nrog ib los yog ob tug neeg siv.
Koj cov kev lag luam yuav txiav txim siab rau qhov chaw database rau koj cov kev xav tau. Saib Database Software Options kom paub ntau ntxiv, nrog rau peb cov npe ntawm Cov Khoom Tsim Kom Zoo Database Online Dawb .