Microsoft SQL neeg rau zaub mov txhawb xya lwm pawg ntawm cov ntaub ntawv. Cov no, binary cov hlua cia rau encoded cov ntaub ntawv sawv cev rau cov khoom binary.
Cov hom ntaub ntawv nyob hauv binary-strings qeb muaj xws li:
- tshuav zog cia ib qho me ntsis nrog tus nqi ntawm 0, 1 lossis NULL .
- binary (n) qhob n the store n bytes ntawm cov ntaub ntawv ceev-loj binary. Cov teb no yuav khaws tau ntau tshaj 8,000 bytes.
- varbinary (n) qhob cia variable nce-ntev binary cov ntaub ntawv ntawm kwv yees li ntawm n bytes. Lawv yuav khaws tau ntau tshaj 8,000 bytes.
- varbinary (max) zog cia variable-ntev binary cov ntaub ntawv ntawm kwv yees li ntawm n bytes. Lawv yuav khaws ntau tshaj 2 GB thiab ua tau cia qhov ntev ntawm cov ntaub ntawv ntxiv nrog rau ob qho ntxiv bytes.
- duab cov duab cia mus txog 2 GB ntawm cov ntaub ntawv thiab nquag siv los khaws txhua hom ntaub ntawv cov ntaub ntawv (tsis yog cov duab).
Cov duab hom yog teem rau deprecation nyob rau hauv ib tug yav tom ntej tso tawm ntawm SQL neeg rau zaub mov. Microsoft engineers pom zoo siv cov varbinary (max) siv hom duab rau kev loj hlob yav tom ntej.
Tsim Nyog Siv
Siv me ntsis txhua zaug thaum koj xav khaws cov khoom-yog-los-tsis muaj cov ntaub ntawv raws li tau pom los ntawm zeroes thiab ones. Siv cov cim binary thaum qhov luaj li cas ntawm txhua tus tseem ceeb. Siv cov kab zauv khoob ntawm qhov loj thaum qhov siab yuav tsum tshaj 8K los yog yuav raug qhov sib txawv ntawm qhov loj ntawm ib daim ntawv.
Sib pauv
T-SQL-lub variant ntawm SQL siv nyob rau hauv Microsoft SQL neeg rau zaub mov -right-los ntawm cov ntaub ntawv thaum koj hloov los ntawm txhua yam hlua hom rau binary lossis varbinary yam. Lwm hom conversion rau ib binary hom yields ib sab laug-ncoo. Qhov no padding yog effected los ntawm kev siv cov hexadecimal zeroes.
Vim hais tias qhov kev hloov dua siab tshiab thiab qhov kev pheej hmoo ntawm kev sib tw, yog qhov kev hloov qis dua tsis txaus, nws yog qhov ua tau hloov dua tshiab yuav ua rau cov teeb meem tsis sib thooj uas tsis cuam tshuam cov lus yuam kev.