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Mwepụta nke DBMS SQLite 3.35

Ntọhapụ nke SQLite 3.35, DBMS dị fechaa emebere dị ka ọba akwụkwọ nkwụnye, ka ebipụtala. A na-ekesa koodu SQLite na ngalaba ọha, ya bụ. enwere ike iji ya na-enweghị mgbochi yana n'efu maka ebumnuche ọ bụla. Nkwado ego maka ndị mmepe SQLite bụ ụlọ ọrụ emebere nke ọma, nke gụnyere ụlọ ọrụ dịka Adobe, Oracle, Mozilla, Bentley na Bloomberg.

Isi mgbanwe:

  • Ọrụ mgbakọ na mwepụ arụnyere arụnyere (log2(), cos(), tg(), exp(), ln(), pow(), wdg) nke enwere ike iji na SQL. Ịkwalite ọrụ arụnyere n'ime ya chọrọ iwulite ya na nhọrọ "-DSQLITE_ENABLE_MATH_FUNCTIONS".
  • Nkwado etinyere maka okwu "ALTER TABLE DROP COLUMN" iji wepụ ogidi na tebụl wee kpochapụ data echekwara na mbụ na kọlụm enyere.
  • A na-agbasawanye arụmọrụ UPSERT (add-or-modify), na-enye ohere site na okwu ndị dị ka "INSERT ... NA esemokwu emela ihe ọ bụla / emelite" ileghara njehie anya ma ọ bụ mee mmelite kama ịtinye ma ọ bụrụ na ọ gaghị ekwe omume ịgbakwunye. data site na "INSERT" (dịka ọmụmaatụ, ọ bụrụ na ndekọ dị adị, Ị nwere ike imelite kama itinye). Ụdị ọhụrụ ahụ na-enye gị ohere ịkọwa ọtụtụ ihe mgbochi mgbochi, nke a ga-ahazi n'usoro. Mgbochi ikpeazụ "ONYE Ọgbaghara" na-enye ohere ịhapụ oke nkọwa esemokwu iji jiri "Melite".
  • Ọrụ HIchapụ, INSERT, na Mmelite na-akwado okwu nlọghachi, nke enwere ike iji gosipụta ọdịnaya nke ndekọ ehichapụ, ntinye, ma ọ bụ gbanwee. Dịka ọmụmaatụ, okwu "tinye n'ime ... id na-eweghachite" ga-eweghachite njirimara nke ahịrị agbakwunyere, na "mmelite ... set price = price * 1.10 nloghachi ọnụahịa" ga-eweghachite uru ọnụahịa gbanwere.
  • Maka nkwupụta okpokoro a na-ahụkarị (CTE), nke na-enye ohere iji usoro nsonaazụ akpọrọ nwa oge akọwapụtara site na iji nkwupụta WITH, nhọrọ nke ụdị “MATERIALIZED” na “NOT MATERIALIZED” ka anabatara. “MATERIALIZED” na-egosi ịchebe ajụjụ akọwapụtara na nlele na tebụl anụ ahụ dị iche wee wepụta data na tebụl a, yana “NOT MATERIALIZED” a ga-eme ajụjụ ugboro ugboro oge ọ bụla enwetara nlele ahụ. SQLite na mbụ adabara na "Ọ BỤGHỊ IKE", mana ọ gbanweela ugbu a ka ọ bụrụ "MATERIALIZED" maka CTE ejiri ihe karịrị otu ugboro.
  • Mbelata oriri ebe nchekwa mgbe ị na-arụ ọrụ VACUUM na ọdụ data nke gụnyere ụkpụrụ TEXT ma ọ bụ BLOB buru ibu.
  • Emeela ọrụ iji bulie arụmọrụ nke optimizer na onye nhazi ajụjụ:
    • Nkwalite agbakwunyere mgbe ị na-eji ọrụ min na max nwere okwu "IN".
    • Mmezu nke nkwupụta EXISTS emelitela ngwa ngwa.
    • Mgbasawanye nke subqueries sitere na UNION okwu niile ejiri dị ka akụkụ nke JOIN.
    • A na-eji ndeksi ahụ mee ihe maka okwu adịghị efu.
    • Gbaa n'aka na "x IS NULL" na "x BỤGHỊ FULL" ka agbanwere ka ọ bụrụ Ụgha ma ọ bụ EZIOKWU maka kọlụm nwere àgwà "Ọ BỤGHỊ ỤLỤ".
    • Mafere ịlele igodo mba ofesi na emelite ma ọ bụrụ na ọrụ ahụ agbanweghị ogidi ndị metụtara igodo mba ofesi.
    • A na-ahapụ ya ịkwaga akụkụ nke ebe mgbochi n'ime subqueries nwere ọrụ windo, ma ọ bụrụhaala na akụkụ ndị ahụ nwere oke na ịrụ ọrụ na ngbanwe na mbipụta nke okwu sitere na PARTITION BY blocks eji na ọrụ windo.
  • Mgbanwe na interface ahịrị iwu:
    • agbakwunyere iwu ".filectrl data_version".
    • Iwu ".otu oge" na ".output" na-akwado ịnyefe mmepụta na onye njikwa a na-akpọ site na iji ọkpọkọ akpọghị aha ("|").
    • Agbakwunyela arụmụka "stmt" na "vmstep" na iwu ".stats" iji gosipụta ọnụ ọgụgụ na nkwupụta okwu na igwe igwe mebere.

isi: opennet.ru

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