Video: Qhov txawv ntawm MySQL thiab mysql yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
MySQL yog RDBMS uas tso cai rau khaws cov ntaub ntawv uas muaj hauv a database txheej txheem. MySQL muab ntau tus neeg siv nkag mus rau databases. Qhov no RDBMS system yog siv nrog kev sib xyaw ua ke ntawm PHP thiab Apache Web Server, nyob rau sab saum toj ntawm Linux faib. MySQL siv SQL lus nug cov database.
Tsis tas li ntawd, puas muaj qhov sib txawv ntawm SQL thiab MySQL?
Qhov sib txawv ntawm MySQL thiab SQL ntawv Hauv luv luv, SQL ntawv yog a lus nug, thaum MySQL yog a database tswj system. SQL ntawv los yog Structured Query Language, as tus npe, is a lus uas yog tsim los tswj kev sib raug zoo databases. MySQL , yog tus lwm tes, yog ib open-source software uas yog raws li lub SQL lus.
Tom qab, lo lus nug yog, yog MySQL ib hom lus lossis database? MySQL yog ib qho chaw qhib dawb Relational Database Management System (RDBMS) uas siv Structured Query Language ( SQL ntawv ). SQL ntawv yog hom lus nrov tshaj plaws rau kev ntxiv, nkag mus thiab tswj cov ntsiab lus hauv database. Nws yog feem ntau sau tseg rau nws cov txheej txheem ceev, pov thawj kev ntseeg tau, yooj yim thiab yooj yim ntawm kev siv.
Kuj Paub, qhov twg yog qhov zoo dua SQL lossis MySQL?
Hais txog kev ua haujlwm, MySQL muaj zoo dua kev ua tau zoo tshaj MsSQL. Hais txog cov ntaub ntawv rov qab, mssql muaj zoo dua rov qab mechanism piv rau MySQL . Qhov tseem ceeb tshaj plaws yog MySQL ua haujlwm ntawm UNIX thiab Linux thaum mssql tsis ua haujlwm ntawm cov OS no. Nws tsis yog hais txog qhov twg ntawm MySQL los yog MS SQL ntawv Server yog zoo dua.
MySQL yog dab tsi thiab vim li cas nws thiaj siv?
MySQL yog ib qho kev sib raug zoo database tswj system raws li SQL - Structured Query Language. Daim ntawv thov yog siv rau ntau lub hom phiaj, suav nrog cov ntaub ntawv khaws cia, e-lag luam, thiab daim ntawv thov nkag. Feem ntau siv rau mySQL Txawm li cas los xij, yog rau lub hom phiaj ntawm lub vev xaib database.
Pom zoo:
Dab tsi yog qhov txawv ntawm qhov sib txawv hauv zos thiab thoob ntiaj teb hauv SQL Server?
Qhov sib txawv hauv zos tau tshaj tawm hauv ib qho kev ua haujlwm whereas Ntiaj teb hloov pauv tau tshaj tawm sab nraum lub luag haujlwm. Cov kev hloov hauv zos tau tsim thaum lub luag haujlwm tau pib ua tiav thiab ploj thaum lub luag haujlwm xaus, ntawm qhov tod tes, Ntiaj teb hloov pauv yog tsim raws li kev tua pib thiab ploj thaum qhov kev pab cuam xaus
Dab tsi yog qhov sib txawv ntawm lub thawv thiab lub thawv ntawv thiab lub thawv ntawv yog dab tsi?
Ib lub thawv thiab cov ntawv nplawm (qee zaum hu ua boxplot) yog ib daim duab uas nthuav tawm cov ntaub ntawv los ntawm tsib lub ntsiab lus. Nyob rau hauv ib lub thawv thiab whisker zajlus: qhov kawg ntawm lub thawv yog lub sab sauv thiab sab quartiles, yog li lub thawv spans lub interquartile ntau yam. qhov nruab nrab yog cim los ntawm ib txoj kab ntsug hauv lub thawv
Dab tsi yog qhov txawv ntawm cov ntaub ntawv hom thiab qhov sib txawv?
Ib qho kev sib txawv yuav tsum muaj cov ntaub ntawv sib txuas nrog nws, piv txwv li nws tuaj yeem muaj cov ntaub ntawv xws li cov lej, lej lej, cov cim thiab lwm yam. Qhov sib txawv ntawm hom Integer khaws cov lej suav thiab tus cim typevariable khaws cov cim tus nqi. Thawj qhov sib txawv ntawm ntau hom ntaub ntawv yog lawv qhov loj me me
Dab tsi yog qhov zoo sib xws thiab qhov txawv ntawm relays thiab PLC yog dab tsi?
Relays yog electro-mechanical keyboards uas muaj coil thiab ob hom kev sib cuag uas tsis yog NO & NC. Tab sis Programmable Logic Controller, PLC yog lub khoos phis tawj me uas tuaj yeem txiav txim siab raws li qhov kev zov me nyuam thiab nws cov tswv yim & tso tawm
Dab tsi yog qhov sib txawv ntawm qhov ntsuas qhov ntsuas thiab qhov ntsuas thib ob?
Primary index: nyob rau hauv ib tug sequentially order file, qhov Performance index uas nws search key qhia cov sequential order ntawm cov ntaub ntawv. Kuj hu ua clustering index. Secondary index: ib qho Performance index uas nws qhov tseem ceeb tshawb nrhiav qhia qhov kev txiav txim sib txawv ntawm qhov kev txiav txim ntawm cov ntaub ntawv. Kuj hu ua non-clustering index