Kutulutsidwa kwa SQLite 3.35, DBMS yopepuka yopangidwa ngati laibulale ya pulagi, kwasindikizidwa. Khodi ya SQLite imagawidwa pagulu la anthu, i.e. itha kugwiritsidwa ntchito popanda zoletsa komanso kwaulere pazifukwa zilizonse. Thandizo lazachuma kwa opanga ma SQLite limaperekedwa ndi bungwe lopangidwa mwapadera, lomwe limaphatikizapo makampani monga Adobe, Oracle, Mozilla, Bentley ndi Bloomberg.
Zosintha zazikulu:
- Zowonjezera masamu (log2(), cos(), tg(), exp(), ln(), pow(), etc.) zomwe zingagwiritsidwe ntchito mu SQL. Kuyang'anira ntchito zomangidwira kumafuna kumanga ndi "-DSQLITE_ENABLE_MATH_FUNCTIONS".
- Kuthandizira kwa mawu akuti "ALTER TABLE DROP COLUMN" kuti muchotse zipilala patebulo ndikuchotsa zomwe zidasungidwa kale pamndandanda womwe wapatsidwa.
- Kukhazikitsa kwa ntchito ya UPSERT (yowonjezera-kapena-modify) kwakulitsidwa, kulola kudzera m'mawu ngati "LOWANI ... PAMODZI PAMODZI POSANGALATSA PAMODZI / KUSINTHA" kunyalanyaza cholakwika kapena kupanga zosintha m'malo moyika ngati sizingatheke kuwonjezera. data kudzera mu "INSERT" (mwachitsanzo, ngati mbiri ilipo kale, m'malo mwa INSERT mutha kupanga UPDATE). Mtundu watsopanowu umakulolani kuti mutchule midadada angapo ON CONFLICT, yomwe idzasinthidwa mwadongosolo. Chomaliza "ON CONFLICT" chipika chimalola kuti tanthauzo la mikangano lichotsedwe kuti mugwiritse ntchito "KONDANI ZAMBIRI".
- Ntchito za DELETE, INSERT ndi UPDATE zimathandizira mawu a RETURNING, omwe angagwiritsidwe ntchito kuwonetsa zomwe zili mu mbiri yochotsedwa, yoyikidwa kapena yosinthidwa. Mwachitsanzo, mawu oti "ikani mu ... id yobwezera" idzabwezera chizindikiritso cha mzere wowonjezeredwa, ndipo "kusintha ... mtengo wokhazikika = mtengo * 1.10 mtengo wobwerera" udzabwezera mtengo wosinthidwa.
- Kwa Common Table Expressions (CTE), zomwe zimalola kugwiritsa ntchito zotsatira zosakhalitsa zotchulidwa pogwiritsa ntchito mawu a WITH, kusankha kwa "MATERIALIZED" ndi "NOT MATERIALIZED" ndikololedwa. "MATERIALIZED" akutanthauza kusungitsa funso lomwe lafotokozedwa muzowonera patebulo lapadera ndikutenga data kuchokera patebuloli, ndipo ndi mafunso obwerezabwereza "NOT MATERIALIZED" azichitika nthawi iliyonse pomwe mawonekedwewo afikiridwa. SQLite poyamba idasinthidwa kukhala "NOT MATERIALIZED", koma tsopano yasintha kukhala "MATERIALIZED" chifukwa ma CTE amagwiritsidwa ntchito kangapo.
- Kuchepetsa kukumbukira kukumbukira pochita ntchito ya VACUUM pamasamba omwe ali ndi ma TEXT kapena BLOB.
- Ntchito yachitika kuti muwonjezere magwiridwe antchito a optimizer ndi query planner:
- Kukhathamiritsa kowonjezera mukamagwiritsa ntchito min ndi max ntchito ndi mawu akuti "IN".
- Kuchita kwa mawu a EXISTS kwafulumizitsa.
- Kukulitsa kwa mawu ang'onoang'ono ochokera ku UNION ALL mawu omwe amagwiritsidwa ntchito ngati gawo la JOIN.
- Mlozerawu umagwiritsidwa ntchito pa mawu akuti IS NOT NULL.
- Imawonetsetsa kuti "x IS NULL" ndi "x IS NOT NULL" asinthidwa kukhala FALSE kapena TRUE pazambiri zomwe zili ndi "NOT NULL".
- Lumphani kuyang'ana makiyi akunja mu UPDATE ngati ntchitoyo sikusintha magawo okhudzana ndi kiyi yakunja.
- Zimaloledwa kusuntha magawo a WHERE block kukhala magawo omwe ali ndi zenera, bola ngati magawowo ali ndi malire pakugwira ntchito ndi zokhazikika ndi makope a mawu ochokera ku PARTITION BY midadada yogwiritsidwa ntchito pawindo.
- Zosintha pamawonekedwe a mzere wolamula:
- Lawonjezedwa ".filectrl data_version" lamulo.
- Malamulo a ".once" ndi ".output" tsopano amathandizira popereka zotuluka kwa chothandizira chotchedwa kugwiritsa ntchito mapaipi osatchulidwa dzina ("|").
- Zotsutsana za "stmt" ndi "vmstep" zawonjezedwa ku lamulo la ".stats" kuti muwonetse ziwerengero za mawu ndi makina owerengera makina.
Source: opennet.ru
