RailsとDBのトランザクション処理

ebisurb17 #ebisurb
https://ebisurb.connpass.com/event/93818/

Transcript

1. RailsͱDBͷτϥϯβΫγϣϯॲཧ 
   &CJTVSC
2. ࡾ୩
   ণฏ
   Έͨʹ
   ͠ΐ͏΁͍
   ͠ΐʔ΁ʔ
   ָఱגࣜձࣾʢݩ'BCMJDʣ
   &OHJOFFS
   ɹ
   !TIPIFJ
3. ࠓ೔ͷ࿩ w.Z42-ͷτϥϯβΫγϣϯʹ͍ͭͯ
   wόϦσʔγϣϯॲཧͱϩοΫͷམͱ݀͠
4. എܠ w ೖۚγεςϜͰΤϥʔ͕ൃੜ
   w .ZTRM
   %VQMJDBUF
   FOUSZ
   bʜ`
   GPS
   LFZ
   bd
   JOEFY`
   */4&35
   ʜ
   w ϩοΫ੍ޚ͕ߦΘΕ͍ͯΔՕॴ
   w ॏෳνΣοΫ΋ߦΘΕ͍ͯΔ
   w ͳͥʁʁʁ
5. ֘౰ͷιʔείʔυʢΠϝʔδʣ def index … ActiveRecord::Base.transaciton do order = Order.find(params[:order_id]) item = Item.lock.find(order.item_id) return … if payment_finished?(order, item) … Settlement.create(…) item.paid end end def payment_finished?(order, item) settlement = Settlement.find_by(order_id: order.id) settlement.present? && item.paid? end
6. ίʔυͷલʹ%#ͷ͓࿩ʜ
7. .Z42-ͷඞਢ஌ࣝᶃɿ෼཭Ϩϕϧ • μʔςΟϦʔυ • ೋͭͷτϥϯβΫγϣϯ͕͋ͬͨͱ͖ʹɺยํͷະίϛοτͷσʔλ͕औಘͰ͖ Δ͜ͱ • ϑΝδʔϦʔυ • τϥϯβΫγϣϯ͕։࢝ͨ͠ޙʹଞ͕ߋ৽ɺ࡟আͯ͠ίϛοτͨ͠σʔλ͕औಘͰ ͖Δ͜ͱ • ϑΝϯτϜϦʔυ • ϑΝδʔϦʔυͷInsert൛ • ϩετΞοϓσʔτ • ଞͷτϥϯβΫγϣϯ͕ίϛοτ͢ΔલͷσʔλͰɺ৽͍͠σʔλΛॻ͖׵͑ͯ͠ ·͏͜ͱ τϥϯβΫγϣϯʹؔ܎͢Δ໰୊
   ʢଞʹ΋΋ͬͱ͋ΔΑʜʣ
8. .Z42-ͷඞਢ஌ࣝᶃɿ෼཭Ϩϕϧ Լʹߦ͘΄ͲτϥϯβΫγϣϯ಺ͰͷσʔλͷҰ؏ੑ͕ߴ͍ ৄ͘͠͸͜͜ಡΜͰ https://dev.mysql.com/doc/refman/5.6/ja/glossary.html#glos_isolation_level .Z42-ʹ͓͚Δ෼཭ϨϕϧͱτϥϯβΫγϣϯ໰୊ͷ༧๷ঢ়گ
9. .Z42-ͷඞਢ஌ࣝᶄɿεφοϓγϣοτ Ͳ͏΍ͬͯϑΝϯτϜϦʔυ͕ղܾ͞Ε͍ͯΔͷ͔ʁʁ 14.2.4 Ұ؏ੑඇϩοΫಡΈऔΓ Ұ؏ੑಡΈऔΓͱ͸ɺInnoDB ͕ϚϧνόʔδϣϯΛ࢖༻ͯ͠ɺ͋Δ࣌఺Ͱͷσʔλϕʔε ͷεφοϓγϣοτΛΫΤϦʔʹఏڙ͢Δ͜ͱΛҙຯ͠·͢ɻΫΤϦʔʹ͸ɺͦͷ࣌఺ΑΓ ΋લʹίϛοτ͞ΕͨτϥϯβΫγϣϯʹΑΔมߋͷΈ͕දࣔ͞Εɺͦͷ࣌఺ΑΓ΋͋ͱͷ τϥϯβΫγϣϯ·ͨ͸ίϛοτ͞Ε͍ͯͳ͍τϥϯβΫγϣϯʹΑΔมߋ͸දࣔ͞Ε·ͤ Μɻ …
 τϥϯβΫγϣϯ෼཭Ϩϕϧ͕ REPEATABLE READ (σϑΥϧτͷϨϕϧ) Ͱ͋Δ৔߹͸ɺ ಉ͡τϥϯβΫγϣϯ಺ͷ͢΂ͯͷҰ؏ੑಡΈऔΓͰɺͦͷτϥϯβΫγϣϯ಺ͷ࠷ॳͷ͜ ͷΑ͏ͳಡΈऔΓͰཱ֬͞Εͨεφοϓγϣοτ͕ಡΈऔΒΕ·͢ɻݱࡏͷτϥϯβΫγϣ ϯΛίϛοτͨ͋͠ͱʹɺ৽͍͠ΫΤϦʔΛൃߦ͢ΔͱɺΫΤϦʔͷ৽͍͠εφοϓγϣο τΛऔಘͰ͖·͢ɻ IUUQTEFWNZTRMDPNEPDSFGNBOKBJOOPECDPOTJTUFOUSFBEIUNM
10. .Z42-ͷඞਢ஌ࣝᶄɿεφοϓγϣοτ উखͳΠϝʔδ εφοϓγϣοτ σʔλϕʔε BIGIN SELECT ~ SELECT ~ UPDATE ~ COMMIT ⁞   ⁠ ⁡
11. վΊͯ֘౰ͷιʔείʔυ def index … ActiveRecord::Base.transaciton do order = Order.find(params[:order_id]) item = Item.lock.find(order.item_id) return … if payment_finished?(order, item) … Settlement.create(…) item.paid end end def payment_finished?(order, item) settlement = Settlement.find_by(order_id: order.id) settlement.present? && item.paid? end ͍ͭͷεφοϓγϣοτʁ ͍ͭͷεφοϓγϣοτʁ
12. ഉଞ੍ޚͱॏෳνΣοΫ εφοϓ γϣοτ σʔλϕʔε εφοϓ γϣοτ τϥϯβΫγϣϯ" τϥϯβΫγϣϯ# 4&-&$5 4&-&$5
    '03
    61%"5& */4&35 61%"5& $0..*5 4&-&$5 4&-&$5
    '03
    61%"5& */4&35 61%"5& $0..*5 4&-&$5 4&-&$5 ϩοΫղ์଴ͪ ⁞   ⁠ ⁡ ⁣ ⁢ ⁤ ⁥ ⁦ ➓ ੔߹ੑΛอͯͳ͍ͭͷ
    εφοϓγϣοτ͕ଘࡏ
13. վΊͯ֘౰ͷιʔείʔυ def index … ActiveRecord::Base.transaciton do order = Order.find(params[:order_id]) item = Item.lock.find(order.item_id) return … if payment_finished?(order, item) … Settlement.create(…) item.paid end end def payment_finished?(order, item) settlement = Settlement.find_by(order_id: order.id) settlement.present? && item.paid? end ผτϥϯβΫγϣϯͷ
    ίϛοτΛ൓өͰ͖ͯͳ͍
14. ղܾࡦ w ࣮૷໘
    w ϩοΫॲཧ͸τϥϯβΫγϣϯͷॳΊʹ࣮ߦ͢Δ
    w '03
    61%"5&͸ϩοΫղ์ޙʹ4&-&$5Λൃߦ͢Δ
    w "DUJWF3FDPSE#BTFUSBOTBDUJPOΑΓ "DUJWF3FDPSE-PDLJOH1FTTJNJTUJDXJUI@MPDLΛ࢖͏
    w ઃܭ໘
    w ςʔϒϧΛ୯Ұ੹೚ʹ͢Δ
    w ςʔϒϧʹΞΫηε͢ΔϦΫΤετΛ੍ݶ͢Δ
15. ·ͱΊ w .Z42-͸Ұ؏ੑಡΈऔΓʹΑΓϑΝϯτϜϦʔυΛ๷ࢭ͍ͯ͠Δ
    w ͦͷཪଆͰ͸εφοϓγϣοτ͕࡞੒͞Ε͍ͯΔ
    w τϥϯβΫγϣϯΛுΔ࣌͸ɺϩοΫͷҐஔʹؾΛ͚ͭΔ
16. ͝੩ௌ͋Γ͕ͱ͏͍͟͝·ͨ͠