ืคึผืจืึธื”ืึธืกื˜ืขืจ > ื‘ืœืึธื’ > ืึทื“ืžื™ื ื™ืกื˜ืจืึทืฆื™ืข > ื‘ืึทืœืึทื ืกื™ื ื’ ืฉืจื™ื™ื‘ื˜ ืื•ืŸ ืœื™ื™ืขื ื˜ ืื™ืŸ ืึท ื“ืึทื˜ืึทื‘ื™ื™ืก

ื‘ืึทืœืึทื ืกื™ื ื’ ืฉืจื™ื™ื‘ื˜ ืื•ืŸ ืœื™ื™ืขื ื˜ ืื™ืŸ ืึท ื“ืึทื˜ืึทื‘ื™ื™ืก

ื‘ืึทืœืึทื ืกื™ื ื’ ืฉืจื™ื™ื‘ื˜ ืื•ืŸ ืœื™ื™ืขื ื˜ ืื™ืŸ ืึท ื“ืึทื˜ืึทื‘ื™ื™ืก
ืื™ืŸ ื“ื™ ืคืจื™ืขืจื“ื™ืงืข ืึทืจื˜ื™ืงืœ ืื™ืš ื“ื™ืกืงืจื™ื™ื‘ื“ ื“ืขื ื‘ืึทื’ืจื™ืฃ ืื•ืŸ ื™ืžืคึผืœืึทืžืขื ื˜ื™ื™ืฉืึทืŸ ืคื•ืŸ ืึท ื“ืึทื˜ืึทื‘ื™ื™ืก ื’ืขื‘ื•ื™ื˜ ืื•ื™ืฃ ื“ื™ ื™ืงืขืจ ืคื•ืŸ ืคืึทื ื’ืงืฉืึทื ื–, ืืœื ื•ื•ื™ ื˜ื™ืฉืŸ ืื•ืŸ ืคืขืœื“ืขืจ ื•ื•ื™ ืื™ืŸ ืจื™ืœื™ื™ืฉืึทื ืึทืœ ื“ืึทื˜ืึทื‘ื™ื™ืกื™ื–. ืขืก ื”ืึธื˜ ืฆื•ื’ืขืฉื˜ืขืœื˜ ืคื™ืœืข ื‘ื™ื™ืฉืคื™ืœืŸ ื•ื•ืึธืก ื•ื•ื™ื™ึทื–ืŸ ื“ื™ ืึทื“ื•ื•ืึทื ื˜ื™ื“ื–ืฉื™ื– ืคื•ืŸ ื“ืขื ืฆื•ื’ืึทื ื’ ืื™ื‘ืขืจ ื“ื™ ืงืœืืกื™ืฉืข. ืคื™ืœืข ื’ืขืคื•ื ืขืŸ ื–ื™ื™ ื ื™ืฉื˜ ืงืึทื ื•ื•ื™ื ืกื™ื ื’ ื’ืขื ื•ื’.

ืื™ืŸ ื“ืขื ืึทืจื˜ื™ืงืœ, ืื™ืš ื•ื•ืขืœ ื•ื•ื™ื™ึทื–ืŸ ืื™ืจ ื•ื•ื™ ื“ืขืจ ื‘ืึทื’ืจื™ืฃ ืึทืœืึทื•ื– ืื™ืจ ืฆื• ื’ืขืฉื•ื•ื™ื ื“ ืื•ืŸ ืงืึทื ื•ื•ื™ื ื™ืึทื ื˜ืœื™ ื•ื•ืึธื’ ืฉืจื™ื™ื‘ื˜ ืื•ืŸ ืœื™ื™ืขื ืขืŸ ืฆื• ื“ื™ ื“ืึทื˜ืึทื‘ื™ื™ืก ืึธืŸ ืงื™ื™ืŸ ืขื ื“ืขืจื•ื ื’ ืื™ืŸ ื“ื™ ืึธืคึผืขืจื™ื™ื˜ื™ื ื’ ืœืึธื’ื™ืง. ืขื ืœืขื›ืข ืคืึทื ื’ืงืฉืึทื ืึทืœื™ื˜ื™ ืื™ื– ืคึผืจื•ื•ื•ื“ ืฆื• ื–ื™ื™ืŸ ื™ืžืคึผืœืึทืžืขื ืึทื“ ืื™ืŸ ืžืึธื“ืขืจืŸ ื’ืขืฉืขืคื˜ DBMSs (ืื™ืŸ ื‘ืึทื–ื•ื ื“ืขืจ, Oracle ืื•ืŸ Microsoft SQL Server). ืื™ืŸ ื“ื™ ืกื•ืฃ ืคื•ืŸ ื“ืขื ืึทืจื˜ื™ืงืœ ืื™ืš ื•ื•ืขื˜ ื•ื•ื™ื™ึทื–ืŸ ืึทื– ื•ื•ืึธืก ื–ื™ื™ ื”ืื‘ืŸ, ืฆื• ืœื™ื™ื’ืŸ ืขืก ืžื™ื™ืœื“ืœื™, ื”ืื˜ ื ื™ืฉื˜ ืึทืจื‘ืขื˜ ืื•ื™ืก ื–ื™ื™ืขืจ ื’ื•ื˜.

ื‘ืึทืฉืจื™ื™ึทื‘ื•ื ื’

ื•ื•ื™ ืคืจื™ืขืจ, ืคึฟืึทืจ ื‘ืขืกืขืจ ืคืืจืฉื˜ืื ื“ ืื™ืš ื•ื•ืขื˜ ืึธื ื”ื™ื™ื‘ืŸ ื“ื™ ื‘ืึทืฉืจื™ื™ึทื‘ื•ื ื’ ืžื™ื˜ ื‘ื™ื™ืฉืคื™ืœืŸ. ื–ืืœ ืก ื–ืึธื’ืŸ ืžื™ืจ ื“ืึทืจืคึฟืŸ ืฆื• ื™ื ืกื˜ืจื•ืžืขื ื˜ ืœืึธื’ื™ืง ื•ื•ืึธืก ื•ื•ืขื˜ ืฆื•ืจื™ืงืงื•ืžืขืŸ ืึท ืจืฉื™ืžื” ืคื•ืŸ ื“ื™ืคึผืึทืจื˜ืžืึทื ืฅ ืžื™ื˜ ื“ื™ ื ื•ืžืขืจ ืคื•ืŸ ืขืžืคึผืœื•ื™ื™ื– ืื™ืŸ ื–ื™ื™ ืื•ืŸ ื–ื™ื™ืขืจ ื’ืึทื ืฅ ื’ืขืฆืึธืœื˜.

ืื™ืŸ ืึท ืคืึทื ื’ืงืฉืึทื ืึทืœ ื“ืึทื˜ืึทื‘ื™ื™ืก ืขืก ื•ื•ืึธืœื˜ ืงื•ืงืŸ ื•ื•ื™ ื“ืึธืก:

CLASS Department โ€˜ะžั‚ะดะตะปโ€™;
name โ€˜ะะฐะธะผะตะฝะพะฒะฐะฝะธะตโ€™ = DATA STRING[100] (Department);

CLASS Employee โ€˜ะกะพั‚ั€ัƒะดะฝะธะบโ€™;
department โ€˜ะžั‚ะดะตะปโ€™ = DATA Department (Employee);
salary โ€˜ะ—ะฐั€ะฟะปะฐั‚ะฐโ€™ =  DATA NUMERIC[10,2] (Employee);

countEmployees โ€˜ะšะพะป-ะฒะพ ัะพั‚ั€ัƒะดะฝะธะบะพะฒโ€™ (Department d) = 
    GROUP SUM 1 IF department(Employee e) = d;
salarySum โ€˜ะกัƒะผะผะฐั€ะฝะฐั ะทะฐั€ะฟะปะฐั‚ะฐโ€™ (Department d) = 
    GROUP SUM salary(Employee e) IF department(e) = d;

SELECT name(Department d), countEmployees(d), salarySum(d);

ื“ื™ ืงืึทืžืคึผืœืขืงืกื™ื˜ื™ ืคื•ืŸ ืขืงืกืึทืงื™ื•ื˜ื™ื ื’ ื“ืขื ืึธื ืคึฟืจืขื’ ืื™ืŸ ืงื™ื™ืŸ DBMS ื•ื•ืขื˜ ื–ื™ื™ืŸ ืขืงื•ื•ื™ื•ื•ืึทืœืขื ื˜ ืฆื• ืึธ (ื ื•ืžืขืจ ืคื•ืŸ ืขืžืคึผืœื•ื™ื™ื–)ื•ื•ื™ื™ึทืœ ื“ืขื ื›ืขื–ืฉื‘ืŸ ืจื™ืงื•ื•ื™ื™ืขืจื– ืกืงืึทื ื™ื ื’ ื“ื™ ื’ืื ืฆืข ื˜ื™ืฉ ืคื•ืŸ ืขืžืคึผืœื•ื™ื™ื– ืื•ืŸ ื“ืขืžืึธืœื˜ ื’ืจื•ืคึผื™ื ื’ ื–ื™ื™ ื“ื•ืจืš ืึธืคึผื˜ื™ื™ืœื•ื ื’. ืขืก ื•ื•ืขื˜ ืื•ื™ืš ื–ื™ื™ืŸ ืขื˜ืœืขื›ืข ืงืœื™ื™ืŸ (ืžื™ืจ ื’ืœื•ื™ื‘ืŸ ืึทื– ืขืก ื–ืขื ืขืŸ ืคื™ืœืข ืžืขืจ ืขืžืคึผืœื•ื™ื™ื– ื•ื•ื™ ื“ื™ืคึผืึทืจื˜ืžืึทื ืฅ) ื”ืขืกืึธืคืข ื“ื™ืคึผืขื ื“ื™ื ื’ ืื•ื™ืฃ ื“ื™ ืื•ื™ืกื“ืขืจื•ื•ื™ื™ืœื˜ ืคึผืœืึทืŸ ืึธ (ืœืึธื’ ื ื•ืžืขืจ ืคื•ืŸ ืขืžืคึผืœื•ื™ื™ื–) ืึธื“ืขืจ ืึธ (ื ื•ืžืขืจ ืคื•ืŸ ื“ื™ืคึผืึทืจื˜ืžืึทื ืฅ) ืคึฟืึทืจ ื’ืจื•ืคึผื™ื ื’ ืื•ืŸ ืึทื–ื•ื™ ืื•ื™ืฃ.

ืขืก ืื™ื– ืงืœืึธืจ ืึทื– ื“ื™ ื“ื•ืจื›ืคื™ืจื•ื ื’ ืึธื•ื•ื•ืขืจื›ืขื“ ืงืขืŸ ื–ื™ื™ืŸ ืึทื ื“ืขืจืฉ ืื™ืŸ ืคืึทืจืฉื™ื“ืขื ืข DBMSs, ืึธื‘ืขืจ ื“ื™ ืงืึทืžืคึผืœืขืงืกื™ื˜ื™ ื•ื•ืขื˜ ื ื™ืฉื˜ ื˜ื•ื™ืฉืŸ ืื™ืŸ ืงื™ื™ืŸ ื•ื•ืขื’.

ืื™ืŸ ื“ื™ ืคืืจื’ืขืœื™ื™ื’ื˜ ื™ืžืคึผืœืึทืžืขื ื˜ื™ื™ืฉืึทืŸ, ื“ื™ ืคืึทื ื’ืงืฉืึทื ืึทืœ DBMS ื•ื•ืขื˜ ื“ื–ืฉืขื ืขืจื™ื™ื˜ ืื™ื™ืŸ ืกืึทื‘ืงื•ื•ืขืจื™ ื•ื•ืึธืก ื•ื•ืขื˜ ืจืขื›ืขื ืขืŸ ื“ื™ ืคืืจืœืื ื’ื˜ ื•ื•ืึทืœื•ืขืก ืคึฟืึทืจ ื“ื™ ืึธืคึผื˜ื™ื™ืœื•ื ื’, ืื•ืŸ ื“ืขืžืึธืœื˜ ืžืึทื›ืŸ ืึท JOIN ืžื™ื˜ ื“ื™ ืึธืคึผื˜ื™ื™ืœื•ื ื’ ื˜ื™ืฉ ืฆื• ื‘ืึทืงื•ืžืขืŸ ื“ืขื ื ืึธืžืขืŸ. ืึธื‘ืขืจ, ืคึฟืึทืจ ื™ืขื“ืขืจ ืคื•ื ืงืฆื™ืข, ื•ื•ืขืŸ ื“ื™ืงืœืขืจื™ื ื’, ืขืก ืื™ื– ืžืขื’ืœืขืš ืฆื• ืฉื˜ืขืœืŸ ืึท ืกืคึผืขืฆื™ืขืœ MATERIALIZED ืžืึทืจืงืขืจ. ื“ืขืจ ืกื™ืกื˜ืขื ื•ื•ืขื˜ ืื•ื™ื˜ืึธืžืึทื˜ื™ืฉ ืฉืึทืคึฟืŸ ืึท ืงืึธืจืึทืกืคึผืึทื ื“ื™ื ื’ ืคืขืœื“ ืคึฟืึทืจ ื™ืขื“ืขืจ ืึทื–ืึท ืคึฟื•ื ืงืฆื™ืข. ื•ื•ืขืŸ ื˜ืฉืึทื ื’ื™ื ื’ ื“ื™ ื•ื•ืขืจื˜ ืคื•ืŸ ืึท ืคึฟื•ื ืงืฆื™ืข, ื“ื™ ื•ื•ืขืจื˜ ืคื•ืŸ ื“ื™ ืคืขืœื“ ื•ื•ืขื˜ ืื•ื™ืš ื˜ื•ื™ืฉืŸ ืื™ืŸ ื“ืขืจ ื–ืขืœื‘ื™ืงืขืจ ื˜ืจืึทื ืกืึทืงื˜ื™ืึธืŸ. ื•ื•ืขืŸ ืึทืงืกืขืกื™ื ื’ ื“ืขื ืคึฟื•ื ืงืฆื™ืข, ื“ื™ ืคืึทืจ-ืงืึทืœืงื™ืึทืœื™ื™ื˜ื™ื“ ืคืขืœื“ ื•ื•ืขื˜ ื–ื™ื™ืŸ ืึทืงืกืขืกื˜.

ืื™ืŸ ื‘ืึทื–ื•ื ื“ืขืจ, ืื•ื™ื‘ ืื™ืจ ืฉื˜ืขืœืŸ MATERIALIZED ืคึฟืึทืจ ืคืึทื ื’ืงืฉืึทื ื– countEmployees ะธ ื’ืขืฆืึธืœื˜ ืกื•ืžืข, ื“ืขืžืึธืœื˜ ืฆื•ื•ื™ื™ ืคืขืœื“ืขืจ ื•ื•ืขื˜ ื–ื™ื™ืŸ ืฆื•ื’ืขื’ืขื‘ืŸ ืฆื• ื“ื™ ื˜ื™ืฉ ืžื™ื˜ ื“ื™ ืจืฉื™ืžื” ืคื•ืŸ ื“ื™ืคึผืึทืจื˜ืžืึทื ืฅ, ื•ื•ืึธืก ื•ื•ืขื˜ ืงืจืึธื ื“ื™ ื ื•ืžืขืจ ืคื•ืŸ ืขืžืคึผืœื•ื™ื™ื– ืื•ืŸ ื–ื™ื™ืขืจ ื’ืึทื ืฅ ื’ืขืฆืึธืœื˜. ื•ื•ืขืŸ ืขืก ืื™ื– ืึท ืขื ื“ืขืจื•ื ื’ ืื™ืŸ ืขืžืคึผืœื•ื™ื™ื–, ื–ื™ื™ืขืจ ืกืึทืœืขืจื™ื– ืึธื“ืขืจ ืึธืคึผื˜ื™ื™ืœื•ื ื’ ืึทืคื™ืœื™ื™ื™ืฉืึทื ื–, ื“ื™ ืกื™ืกื˜ืขื ื•ื•ืขื˜ ืื•ื™ื˜ืึธืžืึทื˜ื™ืฉ ื˜ื•ื™ืฉืŸ ื“ื™ ื•ื•ืึทืœื•ืขืก ืคื•ืŸ ื“ื™ ืคืขืœื“ืขืจ. ื“ื™ ืื•ื™ื‘ืŸ ืึธื ืคึฟืจืขื’ ื•ื•ืขื˜ ืึทืงืกืขืก ื“ื™ ืคืขืœื“ืขืจ ื’ืœื™ื™ึทืš ืื•ืŸ ื•ื•ืขื˜ ื–ื™ื™ืŸ ืขืงืกืึทืงื™ื•ื˜ืึทื“ ืื™ืŸ ืึธ (ื ื•ืžืขืจ ืคื•ืŸ ื“ื™ืคึผืึทืจื˜ืžืึทื ืฅ).

ื•ื•ืึธืก ื–ืขื ืขืŸ ื“ื™ ืจื™ืกื˜ืจื™ืงืฉืึทื ื–? ื‘ืœื•ื™ื– ืื™ื™ืŸ ื–ืึทืš: ืึทื–ืึท ืึท ืคึฟื•ื ืงืฆื™ืข ืžื•ื–ืŸ ื”ืึธื‘ืŸ ืึท ืขื ื“ืœืขืš ื ื•ืžืขืจ ืคื•ืŸ ืึทืจื™ื™ึทื ืฉืจื™ื™ึทื‘ ื•ื•ืึทืœื•ืขืก ืคึฟืึทืจ ื•ื•ืึธืก ื–ื™ื™ึทืŸ ื•ื•ืขืจื˜ ืื™ื– ื“ื™ืคื™ื™ื ื“. ืึทื ื“ืขืจืฉ, ืขืก ื•ื•ืขื˜ ื–ื™ื™ืŸ ืื•ืžืžืขื’ืœืขืš ืฆื• ื‘ื•ื™ืขืŸ ืึท ื˜ื™ืฉ ืžื™ื˜ ืึทืœืข ื–ื™ื™ึทืŸ ื•ื•ืึทืœื•ืขืก, ื•ื•ื™ื™ึทืœ ืขืก ืงืขืŸ ื ื™ืฉื˜ ื–ื™ื™ืŸ ืึท ื˜ื™ืฉ ืžื™ื˜ ืึท ื™ื ืคืึทื ืึทื˜ ื ื•ืžืขืจ ืคื•ืŸ ืจืึธื•ื–.

ื‘ื™ื™ึทืฉืคึผื™ืœ:

employeesCount โ€˜ะšะพะปะธั‡ะตัั‚ะฒะพ ัะพั‚ั€ัƒะดะฝะธะบะพะฒ ั ะทะฐั€ะฟะปะฐั‚ะพะน > Nโ€™ (Department d, NUMERIC[10,2] N) = 
    GROUP SUM salary(Employee e) IF department(e) = d AND salary(e) > N;

ื“ื™ ืคึฟื•ื ืงืฆื™ืข ืื™ื– ื“ื™ืคื™ื™ื ื“ ืคึฟืึทืจ ืึท ื™ื ืคืึทื ืึทื˜ ื ื•ืžืขืจ ืคื•ืŸ ื•ื•ืึทืœื•ืขืก ืคื•ืŸ N (ืœืžืฉืœ, ืงื™ื™ืŸ ื ืขื’ืึทื˜ื™ื•ื• ื•ื•ืขืจื˜ ืื™ื– ืคึผืึทืกื™ืง). ื“ืขืจื™ื‘ืขืจ, ืื™ืจ ืงืขื ืขืŸ ื ื™ืฉื˜ ืฉื˜ืขืœืŸ MATERIALIZED ืื•ื™ืฃ ืขืก. ืึทื–ื•ื™ ื“ืึธืก ืื™ื– ืึท ืœืึทื“ื–ืฉื™ืงืึทืœ ื‘ืึทื’ืจืขื ืขืฆื•ื ื’, ื ื™ืฉื˜ ืึท ื˜ืขื›ื ื™ืฉ (ื“ืึธืก ืื™ื–, ื ื™ืฉื˜ ื•ื•ื™ื™ึทืœ ืžื™ืจ ืงืขืŸ ื ื™ืฉื˜ ื™ื ืกื˜ืจื•ืžืขื ื˜ ืขืก). ืึทื ื“ืขืจืฉ, ืขืก ื–ืขื ืขืŸ ืงื™ื™ืŸ ืจื™ืกื˜ืจื™ืงืฉืึทื ื–. ืื™ืจ ืงืขื ืขืŸ ื ื•ืฆืŸ ื’ืจื•ืคึผืขืก, ืกืึธืจื˜ื™ื ื’, AND ืื•ืŸ OR, ืฆืขื˜ื™ื™ืœื•ื ื’, ืจืขืงื•ืจืกื™ืึธืŸ, ืขื˜ืง.

ืคึฟืึทืจ ื‘ื™ื™ึทืฉืคึผื™ืœ, ืื™ืŸ ืคึผืจืึธื‘ืœืขื 2.2 ืคื•ืŸ ื“ื™ ืคืจื™ืขืจื“ื™ืงืข ืึทืจื˜ื™ืงืœ, ืื™ืจ ืงืขื ืขืŸ ืฉื˜ืขืœืŸ MATERIALIZED ืื•ื™ืฃ ื‘ื™ื™ื“ืข ืคืึทื ื’ืงืฉืึทื ื–:

bought 'ะšัƒะฟะธะป' (Customer c, Product p, INTEGER y) = 
    GROUP SUM sum(Detail d) IF 
        customer(order(d)) = c AND 
        product(d) = p AND 
        extractYear(date(order(d))) = y MATERIALIZED;
rating 'ะ ะตะนั‚ะธะฝะณ' (Customer c, Product p, INTEGER y) = 
    PARTITION SUM 1 ORDER DESC bought(c, p, y), p BY c, y MATERIALIZED;
SELECT contactName(Customer c), name(Product p) WHERE rating(c, p, 1997) < 3;

ื“ื™ ืกื™ืกื˜ืขื ื–ื™ืš ื•ื•ืขื˜ ืžืึทื›ืŸ ืื™ื™ืŸ ื˜ื™ืฉ ืžื™ื˜ ื˜ื™ืคึผ ืฉืœื™ืกืœืขืŸ ืงื•ื™ื ืข, ืคึผืจืึธื“ื•ืงื˜ ะธ ื™ื ื˜ืขื’ืขืจ, ื•ื•ืขื˜ ืœื™ื™ื’ืŸ ืฆื•ื•ื™ื™ ืคืขืœื“ืขืจ ืฆื• ืขืก ืื•ืŸ ื•ื•ืขื˜ ื“ืขืจื”ื™ื™ึทื ื˜ื™ืงืŸ ื“ื™ ืคืขืœื“ ื•ื•ืึทืœื•ืขืก ืื™ืŸ ื–ื™ื™ ืžื™ื˜ ืงื™ื™ืŸ ืขื ื“ืขืจื•ื ื’ืขืŸ. ื•ื•ืขืŸ ื•ื•ื™ื™ึทื˜ืขืจ ืจื•ืคื˜ ืฆื• ื“ื™ ืคืึทื ื’ืงืฉืึทื ื– ื–ืขื ืขืŸ ื’ืขืžืื›ื˜, ื–ื™ื™ ื•ื•ืขืœืŸ ื ื™ืฉื˜ ื–ื™ื™ืŸ ืงืึทืœืงื™ืึทืœื™ื™ื˜ื™ื“, ืึธื‘ืขืจ ื“ื™ ื•ื•ืึทืœื•ืขืก ื•ื•ืขื˜ ื–ื™ื™ืŸ ืœื™ื™ืขื ืขืŸ ืคึฟื•ืŸ ื“ื™ ืงืึธืจืึทืกืคึผืึทื ื“ื™ื ื’ ืคืขืœื“ืขืจ.

ืžื™ื˜ ื“ืขื ืžืขืงืึทื ื™ื–ืึทื, ืื™ืจ ืงืขื ืขืŸ, ืœืžืฉืœ, ื‘ืึทืงื•ืžืขืŸ ื‘ืึทืคืจื™ื™ึทืขืŸ ืคื•ืŸ ืจืขืงื•ืจืกื™ืึธื ืก (CTE) ืื™ืŸ ืคึฟืจืื’ืŸ. ืื™ืŸ ื‘ืึทื–ื•ื ื“ืขืจ, ื‘ืึทื˜ืจืึทื›ื˜ืŸ ื’ืจื•ืคึผืขืก ื•ื•ืึธืก ืคืึธืจืขื ืึท ื‘ื•ื™ื ื ื™ืฆืŸ ื“ื™ ืงื™ื ื“ / ืคืึธื˜ืขืจ ืฉื™ื™ื›ื•ืช (ื™ืขื“ืขืจ ื’ืจื•ืคึผืข ื”ืื˜ ืึท ืœื™ื ืง ืฆื• ื–ื™ื™ืŸ ืคืึธื˜ืขืจ):

parent = DATA Group (Group);

ืื™ืŸ ืึท ืคืึทื ื’ืงืฉืึทื ืึทืœ ื“ืึทื˜ืึทื‘ื™ื™ืก, ืจืขืงื•ืจืกื™ืึธืŸ ืœืึธื’ื™ืง ืงืขื ืขืŸ ื–ื™ื™ืŸ ืกืคึผืขืกื™ืคื™ืขื“ ื•ื•ื™ ื’ื™ื™ื˜:

level (Group child, Group parent) = RECURSION 1l IF child IS Group AND parent == child
                                                             STEP 2l IF parent == parent($parent);
isParent (Group child, Group parent) = TRUE IF level(child, parent) MATERIALIZED;

ื–ื™ื ื˜ ืคึฟืึทืจ ื“ื™ ืคึฟื•ื ืงืฆื™ืข ืื™ื–ืคึผืึทืจืขื ื˜ ืื™ื– ืื ื’ืขืฆื™ื™ื›ื ื˜ MATERIALIZED, ื“ืขืžืึธืœื˜ ืึท ื˜ื™ืฉ ืžื™ื˜ ืฆื•ื•ื™ื™ ืฉืœื™ืกืœืขืŸ (ื’ืจื•ืคึผืขืก) ื•ื•ืขื˜ ื–ื™ื™ืŸ ื‘ืืฉืืคืŸ ืคึฟืึทืจ ืื™ื, ืื™ืŸ ื•ื•ืึธืก ื“ื™ ืคืขืœื“ ืื™ื–ืคึผืึทืจืขื ื˜ ื•ื•ืขื˜ ื–ื™ื™ืŸ ืืžืช ื ืึธืจ ืื•ื™ื‘ ื“ืขืจ ืขืจืฉื˜ืขืจ ืฉืœื™ืกืœ ืื™ื– ืึท ืงื™ื ื“ ืคื•ืŸ ื“ื™ ืจื’ืข. ื“ื™ ื ื•ืžืขืจ ืคื•ืŸ ืื™ื™ื ืกืŸ ืื™ืŸ ื“ืขื ื˜ื™ืฉ ื•ื•ืขื˜ ื–ื™ื™ืŸ ื’ืœื™ื™ึทืš ืฆื• ื“ื™ ื ื•ืžืขืจ ืคื•ืŸ ื’ืจื•ืคึผืขืก ื’ืขืžืขืจื˜ ืžื™ื˜ ื“ื™ ื“ื•ืจื›ืฉื ื™ื˜ืœืขืš ื˜ื™ืคืงื™ื™ึทื˜ ืคื•ืŸ ื“ืขื ื‘ื•ื™ื. ืื•ื™ื‘ ืื™ืจ ื“ืึทืจืคึฟืŸ, ืœืžืฉืœ, ืฆื• ืฆื™ื™ืœืŸ ื“ื™ ื ื•ืžืขืจ ืคื•ืŸ ืงื™ื ื“ืกืงื™ื ื“ืขืจ ืคื•ืŸ ืึท ื–ื™ื›ืขืจ ื’ืจื•ืคึผืข, ืื™ืจ ืงืขื ืขืŸ ื ื•ืฆืŸ ื“ืขื ืคึฟื•ื ืงืฆื™ืข:

childrenCount (Group g) = GROUP SUM 1 IF isParent(Group child, g);

ืขืก ื•ื•ืขื˜ ื–ื™ื™ืŸ ืงื™ื™ืŸ CTE ืื™ืŸ ื“ื™ SQL ืึธื ืคึฟืจืขื’. ืึทื ืฉื˜ืึธื˜ ืขืก ื•ื•ืขื˜ ื–ื™ื™ืŸ ืึท ืคึผืฉื•ื˜ GROUP BY.

ืžื™ื˜ ื“ืขื ืžืขืงืึทื ื™ื–ืึทื, ืื™ืจ ืงืขื ืขืŸ ืื•ื™ืš ืœื™ื™ื›ื˜ ื“ื™ื ืึธืจืžืึทืœื™ื™ื– ื“ื™ ื“ืึทื˜ืึทื‘ื™ื™ืก ืื•ื™ื‘ ื ื™ื™ื˜ื™ืง:

CLASS Order 'ะ—ะฐะบะฐะท';
date 'ะ”ะฐั‚ะฐ' = DATA DATE (Order);

CLASS OrderDetail 'ะกั‚ั€ะพะบะฐ ะทะฐะบะฐะทะฐ';
order 'ะ—ะฐะบะฐะท' = DATA Order (OrderDetail);
date 'ะ”ะฐั‚ะฐ' (OrderDetail d) = date(order(d)) MATERIALIZED INDEXED;

ื•ื•ืขืŸ ืจื•ืคืŸ ืึท ืคึฟื•ื ืงืฆื™ืข ื“ืึทื˜ืข ืคึฟืึทืจ ื“ื™ ืกื“ืจ ืฉื•ืจื”, ื“ื™ ืคืขืœื“ ืคึฟืึทืจ ื•ื•ืึธืก ืขืก ืื™ื– ืึทืŸ ืื™ื ื“ืขืงืก ื•ื•ืขื˜ ื–ื™ื™ืŸ ืœื™ื™ืขื ืขืŸ ืคื•ืŸ ื“ื™ ื˜ื™ืฉ ืžื™ื˜ ืกื“ืจ ืฉื•ืจื•ืช. ื•ื•ืขืŸ ื“ื™ ืกื“ืจ ื“ืึทื˜ืข ืขื ื“ืขืจื•ื ื’ืขืŸ, ื“ื™ ืกื™ืกื˜ืขื ื–ื™ืš ื•ื•ืขื˜ ืื•ื™ื˜ืึธืžืึทื˜ื™ืฉ ืจื™ืงืึทืœืงื™ืึทืœื™ื™ื˜ ื“ื™ ื“ื™ื ืึธืจืžืึทืœื™ื™ื–ื“ ื“ืึทื˜ืข ืื™ืŸ ื“ื™ ืฉื•ืจื”.

ืึทื“ื•ื•ืึทื ื˜ืึทื’ืขืก

ื•ื•ืึธืก ืื™ื– ื“ืขืจ ื’ืื ืฆืขืจ ืžืขืงืึทื ื™ื–ืึทื ืคึฟืึทืจ? ืื™ืŸ ืงืœืึทืกื™ืฉ ื“ื‘ืžืก, ืึธืŸ ืจื™ืจื™ื™ื˜ื™ื ื’ ืงื•ื•ื™ืจื™ื–, ืึท ื“ืขื•ื•ืขืœืึธืคึผืขืจ ืึธื“ืขืจ ื“ื‘ืึท ืงืขื ืขืŸ ื‘ืœื•ื™ื– ื˜ื•ื™ืฉืŸ ื™ื ื“ืขืงืกื™ื–, ื‘ืึทืฉื˜ื™ืžืขืŸ ืกื˜ืึทื˜ื™ืกื˜ื™ืง ืื•ืŸ ื–ืึธื’ืŸ ื“ื™ ืึธื ืคึฟืจืขื’ ืคึผืœืึทื ืขืจ ื•ื•ื™ ืฆื• ื•ื™ืกืคื™ืจืŸ ื–ื™ื™ (ืื•ืŸ ื”ื™ื ืฅ ื–ืขื ืขืŸ ื‘ืœื•ื™ื– ื‘ื ื™ืžืฆื ืื™ืŸ ื’ืขืฉืขืคื˜ ื“ื‘ืžืก). ื ื™ื˜ ืงื™ื™ืŸ ืขื ื™ืŸ ื•ื•ื™ ืฉื•ื•ืขืจ ื–ื™ื™ ืคึผืจื•ื‘ื™ืจืŸ, ื–ื™ื™ ื•ื•ืขืœืŸ ื ื™ืฉื˜ ืงืขื ืขืŸ ืฆื• ืคืึทืจืขื ื“ื™ืงืŸ ื“ื™ ืขืจืฉื˜ืขืจ ืึธื ืคึฟืจืขื’ ืื™ืŸ ื“ืขื ืึทืจื˜ื™ืงืœ ืื™ืŸ ืึธ (ืฆืึธืœ ืคื•ืŸ ื“ื™ืคึผืึทืจื˜ืžืึทื ืฅ) ืึธืŸ ื˜ืฉืึทื ื’ื™ื ื’ ืงื•ื•ื™ืจื™ื– ืึธื“ืขืจ ืึทื“ื™ื ื’ ื˜ืจื™ื’ืขืจื–. ืื™ืŸ ื“ื™ ืคืืจื’ืขืœื™ื™ื’ื˜ ืกื›ืขืžืข, ืื™ืŸ ื“ืขืจ ืึทื ื˜ื•ื•ื™ืงืœื•ื ื’ ื‘ื™ื ืข ืื™ืจ ื˜ืึธืŸ ื ื™ื˜ ื”ืึธื‘ืŸ ืฆื• ื˜ืจืึทื›ื˜ืŸ ื•ื•ืขื’ืŸ ื“ื™ ื“ืึทื˜ืŸ ืกื˜ืึธืจื™ื“ื–ืฉ ืกื˜ืจื•ืงื˜ื•ืจ ืื•ืŸ ื•ื•ืึธืก ืึทื’ื’ืจืขื’ืึทื˜ื™ืึธื ืก ืฆื• ื ื•ืฆืŸ. ืึทืœืข ื“ืขื ืงืขื ืขืŸ ื–ื™ื™ืŸ ืœื™ื™ื›ื˜ ื˜ืฉื™ื™ื ื“ื–ืฉื“ ืื•ื™ืฃ ื“ื™ ืคืœื™ืขืŸ, ื’ืœื™ื™ึทืš ืื™ืŸ ืึธืคึผืขืจืึทืฆื™ืข.

ืื™ืŸ ืคื™ืจ ืขืก ืงื•ืงื˜ ื•ื•ื™ ื“ืึธืก. ืขื˜ืœืขื›ืข ืžืขื ื˜ืฉืŸ ืึทื ื˜ื•ื•ื™ืงืœืขืŸ ืœืึธื’ื™ืง ื’ืœื™ื™ึทืš ื‘ืื–ื™ืจื˜ ืื•ื™ืฃ ื“ื™ ืึทืจื‘ืขื˜ ืื™ืŸ ื”ืึทื ื˜. ื–ื™ื™ ื˜ืึธืŸ ื ื™ื˜ ืคึฟืึทืจืฉื˜ื™ื™ืŸ ืึทืœื’ืขืจื™ื“ืึทืžื– ืื•ืŸ ื–ื™ื™ืขืจ ืงืึทืžืคึผืœืขืงืกื™ื˜ื™, ื ื™ื˜ ื“ื•ืจื›ืคื™ืจื•ื ื’ ืคึผืœืึทื ื–, ืึธื“ืขืจ ื˜ื™ื™ืคึผืก ืคื•ืŸ ื“ื–ืฉื•ื™ื ืฅ, ืื“ืขืจ ืงื™ื™ืŸ ืื ื“ืขืจืข ื˜ืขื›ื ื™ืฉ ืงืึธืžืคึผืึธื ืขื ื˜. ื“ื™ ืžืขื ื˜ืฉืŸ ื–ืขื ืขืŸ ืžืขืจ ื’ืขืฉืขืคื˜ ืึทื ืึทืœื™ืก ื•ื•ื™ ื“ืขื•ื•ืขืœืึธืคึผืขืจืก. ื“ืขืจื ืึธืš, ืึทืœืข ื“ืขื ื’ื™ื™ื˜ ืื™ืŸ ื˜ืขืกื˜ื™ื ื’ ืึธื“ืขืจ ืึธืคึผืขืจืึทืฆื™ืข. ื™ื ื™ื™ื‘ืึทืœื– ืœืึธื’ื™ื ื’ ืคื•ืŸ ืœืึทื ื’-ืคืœื™ืกื ื“ื™ืง ืงื•ื•ื™ืจื™ื–. ื•ื•ืขืŸ ืึท ืœืึทื ื’ ืึธื ืคึฟืจืขื’ ืื™ื– ื“ื™ื˜ืขืงื˜ืึทื“, ืื ื“ืขืจืข ืžืขื ื˜ืฉืŸ (ืžืขืจ ื˜ืขื›ื ื™ืฉ - ื™ืกืขื ืฉืึทืœื™ ื“ื‘ืึท) ื‘ืึทืฉืœื™ืกืŸ ืฆื• ื’ืขื‘ืŸ MATERIALIZED ืื•ื™ืฃ ืขื˜ืœืขื›ืข ื™ื ื˜ืขืจืžื™ื“ื™ื™ื˜ ืคื•ื ืงืฆื™ืข. ื“ืึธืก ืกืœืึธื•ื– ืึทืจืึธืคึผ ื“ื™ ืจืขืงืึธืจื“ื™ื ื’ ืึท ื‘ื™ืกืœ (ื•ื•ื™ื™ึทืœ ืขืก ืจื™ืงื•ื•ื™ื™ืขืจื– ืึทืคึผื“ื™ื™ื˜ื™ื ื’ ืึทืŸ ื ืึธืš ืคืขืœื“ ืื™ืŸ ื“ื™ ื˜ืจืึทื ืกืึทืงื˜ื™ืึธืŸ). ืึธื‘ืขืจ, ื ื™ื˜ ื‘ืœื•ื™ื– ื“ื™ ืึธื ืคึฟืจืขื’ ืื™ื– ื‘ืื˜ื™ื™ื˜ื™ืง ืกืคึผื™ื“ื–, ืึธื‘ืขืจ ืื•ื™ืš ืึทืœืข ืื ื“ืขืจืข ื•ื•ืึธืก ื ื•ืฆืŸ ื“ืขื ืคึฟื•ื ืงืฆื™ืข. ืื™ืŸ ื“ืขืจ ื–ืขืœื‘ื™ืงืขืจ ืฆื™ื™ื˜, ืขืก ืื™ื– ืœืขืคื™ืขืจืขืš ื’ืจื™ื ื’ ืฆื• ื‘ืึทืฉืœื™ืกืŸ ื•ื•ืึธืก ืคื•ื ืงืฆื™ืข ืฆื• ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–. ืฆื•ื•ื™ื™ ื”ื•ื™ืคึผื˜ ืคึผืึทืจืึทืžืขื˜ืขืจืก: ื“ื™ ื ื•ืžืขืจ ืคื•ืŸ ืžืขื’ืœืขืš ืึทืจื™ื™ึทื ืฉืจื™ื™ึทื‘ ื•ื•ืึทืœื•ืขืก (ื“ืึธืก ืื™ื– ื•ื•ื™ ืคื™ืœืข ืจืขืงืึธืจื“ืก ื•ื•ืขื˜ ื–ื™ื™ืŸ ืื™ืŸ ื“ื™ ืงืึธืจืึทืกืคึผืึทื ื“ื™ื ื’ ื˜ื™ืฉ), ืื•ืŸ ื•ื•ื™ ืึธืคื˜ ืขืก ืื™ื– ื’ืขื ื™ืฆื˜ ืื™ืŸ ืื ื“ืขืจืข ืคืึทื ื’ืงืฉืึทื ื–.

ืึทื ืึทืœืึธื’ื•ืขืก

ืžืึธื“ืขืจืŸ ื’ืขืฉืขืคื˜ ื“ื‘ืžืก ื”ืึธื‘ืŸ ืขื ืœืขืš ืžืขืงืึทื ื™ื–ืึทืžื–: ืžืึทื˜ืขืจื™ืึทืœื™ื–ืขื“ ืžื™ื™ื ื•ื ื’ ืžื™ื˜ ืฉื ืขืœ ืจื™ืคืจืขืฉื™ื ื’ (ืึธืจืึทืงืœืข) ืื•ืŸ ื™ื ื“ืขืงืกืขื“ ืžื™ื™ื ื•ื ื’ (ืžื™ื™ืงืจืึธื•ืกืึธืคื˜ ืกืงืœ ืกืขืจื•ื•ื™ืจืขืจ). ืื™ืŸ PostgreSQL, MATERIALIZED VIEW ืงืขื ืขืŸ ื ื™ื˜ ื–ื™ื™ืŸ ื“ืขืจื”ื™ื™ึทื ื˜ื™ืงื˜ ืื™ืŸ ืึท ื˜ืจืึทื ืกืึทืงื˜ื™ืึธืŸ, ืึธื‘ืขืจ ื‘ืœื•ื™ื– ืื•ื™ืฃ ื‘ืขื˜ืŸ (ืื•ืŸ ืืคื™ืœื• ืžื™ื˜ ื–ื™ื™ืขืจ ืฉื˜ืจืขื ื’ ืจื™ืกื˜ืจื™ืงืฉืึทื ื–), ืึทื–ื•ื™ ืžื™ืจ ื˜ืึธืŸ ื ื™ื˜ ื‘ืึทื˜ืจืึทื›ื˜ืŸ ืขืก. ืื‘ืขืจ ื–ื™ื™ ื”ืึธื‘ืŸ ืขื˜ืœืขื›ืข ืคืจืื‘ืœืขืžืขืŸ ื•ื•ืึธืก ื‘ืื˜ื™ื™ื˜ื™ืง ื‘ืึทื’ืจืขื ืขืฆืŸ ื–ื™ื™ืขืจ ื ื•ืฆืŸ.

ืขืจืฉื˜ืขืจ, ืื™ืจ ืงืขื ืขืŸ ื ืึธืจ ื’ืขื‘ืŸ ืžืึทื˜ื™ืจื™ืึทืœื™ื–ื™ื™ืฉืึทืŸ ืื•ื™ื‘ ืื™ืจ ื”ืึธื˜ ืฉื•ื™ืŸ ื‘ืืฉืืคืŸ ืึท ืจืขื’ื•ืœืขืจ VIEW. ืึทื ื“ืขืจืฉ, ืื™ืจ ื•ื•ืขื˜ ื”ืึธื‘ืŸ ืฆื• ืจื™ืจื™ื™ื˜ ื“ื™ ืจื•ืขืŸ ืจื™ืงื•ื•ืขืก ืฆื• ืึทืงืกืขืก ื“ื™ ื ื™ื™ ื‘ืืฉืืคืŸ ืžื™ื™ื ื•ื ื’ ืฆื• ื ื•ืฆืŸ ื“ืขื ืžืึทื˜ื™ืจื™ืึทืœื™ื–ื™ื™ืฉืึทืŸ. ืึธื“ืขืจ ืœืึธื–ืŸ ืึทืœืฅ ื•ื•ื™ ืขืก ืื™ื–, ืึธื‘ืขืจ ืขืก ื•ื•ืขื˜ ื–ื™ื™ืŸ ืœืคึผื—ื•ืช ื™ื ื™ืคืขืงื˜ื™ื•ื• ืื•ื™ื‘ ืขืก ื–ืขื ืขืŸ ื–ื™ื›ืขืจ ืคืึทืจ-ืงืึทืœืงื™ืึทืœื™ื™ื˜ื™ื“ ื“ืึทื˜ืŸ, ืึธื‘ืขืจ ืคื™ืœืข ืคึฟืจืื’ืŸ ื˜ืึธืŸ ื ื™ื˜ ืฉื˜ืขื ื“ื™ืง ื ื•ืฆืŸ ืขืก, ืึธื‘ืขืจ ืจื™ืงืึทืœืงื™ืึทืœื™ื™ื˜ ืขืก.

ืฆื•ื•ื™ื™ื˜ื ืก, ื–ื™ื™ ื”ืึธื‘ืŸ ืึท ืจื™ื–ื™ืง ื ื•ืžืขืจ ืคื•ืŸ ืจื™ืกื˜ืจื™ืงืฉืึทื ื–:

ืึธืจืึทืงืœ

5.3.8.4 ืึทืœื’ืขืžื™ื™ื ืข ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื•ื™ืฃ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ

ื“ื™ ื“ื™ืคื™ื™ื ื™ื ื’ ืึธื ืคึฟืจืขื’ ืคื•ืŸ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืื™ื– ืœื™ืžื™ื˜ืขื“ ื•ื•ื™ ื’ื™ื™ื˜:

  • ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ืจืขืคืขืจืขื ืฆืŸ ืฆื• ื ื™ื˜-ืจื™ืคึผื™ื˜ื™ื ื’ ืื•ื™ืกื“ืจื•ืงืŸ ื•ื•ื™ SYSDATE ืื•ืŸ ROWNUM.
  • ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ืจืขืคืขืจืขื ืฆืŸ ืฆื• RAW or LONG RAW ื“ืึทื˜ืŸ ื˜ื™ื™ืคึผืก.
  • ืขืก ืงืขืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ืึท SELECT ืจืฉื™ืžื” ืกื•ื‘ืงื•ื•ืขืจื™.
  • ืขืก ืงืขืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ืึทื ืึทืœื™ืกื™ืก ืคืึทื ื’ืงืฉืึทื ื– (ืœืžืฉืœ, RANK) ืื™ืŸ ื“ื™ SELECT ืคึผืึทืจืึทื’ืจืึทืฃ.
  • ืขืก ืงืขืŸ ื ื™ืฉื˜ ื“ืขืจืžืึธื ืขืŸ ืึท ื˜ื™ืฉ ืื•ื™ืฃ ื•ื•ืึธืก ืึทืŸ XMLIndex ืื™ื ื“ืขืงืก ืื™ื– ื“ื™ืคื™ื™ื ื“.
  • ืขืก ืงืขืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ืึท MODEL ืคึผืึทืจืึทื’ืจืึทืฃ.
  • ืขืก ืงืขืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ืึท HAVING ืคึผื•ื ืงื˜ ืžื™ื˜ ืึท ืกืึทื‘ืงื•ื•ืขืจื™.
  • ืขืก ืงืขืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ื ืขืกื˜ืขื“ ืงื•ื•ื™ืจื™ื– ื•ื•ืึธืก ื”ืึธื‘ืŸ ANY, ALL, ืื“ืขืจ NOT EXISTS.
  • ืขืก ืงืขืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ืึท [START WITH โ€ฆ] CONNECT BY ืคึผืึทืจืึทื’ืจืึทืฃ.
  • ืขืก ืงืขืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ืงื™ื™ืคืœ ื“ืขื˜ืึทืœ ื˜ื™ืฉืŸ ืื™ืŸ ืคืึทืจืฉื™ื“ืขื ืข ื–ื™ื™ื˜ืœืขืš.
  • ON COMMIT ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืงืขื ืขืŸ ื ื™ืฉื˜ ื”ืึธื‘ืŸ ื•ื•ื™ื™ึทื˜ ื“ืขื˜ืึทืœ ื˜ื™ืฉืŸ.
  • ื ืขืกื˜ืขื“ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื•ื–ืŸ ื”ืึธื‘ืŸ ืึท ืคืึทืจื‘ื™ื ื“ืŸ ืึธื“ืขืจ ื’ืขืžื™ื™ื ื–ืึทื.
  • ืžืึทื˜ืขืจื™ืึทืœื™ื–ืขื“ ืคืึทืจื‘ื™ื ื“ืŸ ืงื•ืงืŸ ืื•ืŸ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ื’ืขืžื™ื™ื ื–ืึทื ืงื•ืงืŸ ืžื™ื˜ ืึท GROUP BY ืคึผื•ื ืงื˜ ืงืขื ืขืŸ ื ื™ื˜ ืื•ื™ืกืงืœื™ื™ึทื‘ืŸ ืคื•ืŸ ืึทืŸ ืื™ื ื“ืขืงืก-ืึธืจื’ืึทื ื™ื–ื™ืจื˜ ื˜ื™ืฉ.

5.3.8.5 ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื•ื™ืฃ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ ืื•ื™ืฃ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ ื“ื–ืฉื•ื™ื ืก ื‘ืœื•ื™ื–

ื“ื™ืคื™ื™ื ื™ื ื’ ืคึฟืจืื’ืŸ ืคึฟืึทืจ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ ื“ื–ืฉื•ื™ื ืฅ ื‘ืœื•ื™ื– ืื•ืŸ ืงื™ื™ืŸ ืึทื’ื’ืจืขื’ืึทืฅ ื”ืึธื‘ืŸ ื“ื™ ืคืืœื’ืขื ื“ืข ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื•ื™ืฃ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ:

  • ื›ืœ ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืคื•ืŸ ยซืึทืœื’ืขืžื™ื™ื ืข ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื•ื™ืฃ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ".
  • ื–ื™ื™ ืงืขื ืขืŸ ื ื™ืฉื˜ ื”ืึธื‘ืŸ GROUP BY ืงืœืึธื–ื™ื– ืึธื“ืขืจ ืึทื’ื’ืจืขื’ืึทืฅ.
  • ืจืึธื•ื•ื™ื“ืก ืคื•ืŸ ืึทืœืข ื“ื™ ื˜ื™ืฉืŸ ืื™ืŸ ื“ื™ FROM ืจืฉื™ืžื” ืžื•ื–ืŸ ื“ืขืจืฉื™ื™ึทื ืขืŸ ืื™ืŸ ื“ื™ SELECT ืจืฉื™ืžื” ืคื•ืŸ ื“ื™ ืึธื ืคึฟืจืขื’.
  • ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืœืึธื’ืก ืžื•ื–ืŸ ืขืงืกื™ืกื˜ื™ืจืŸ ืžื™ื˜ ืจืึธื•ื•ื™ื“ืก ืคึฟืึทืจ ืึทืœืข ื“ื™ ื‘ืึทื–ืข ื˜ื™ืฉืŸ ืื™ืŸ ื“ื™ FROM ืจืฉื™ืžื” ืคื•ืŸ ื“ื™ ืึธื ืคึฟืจืขื’.
  • ืื™ืจ ืงืขื ืขืŸ ื ื™ืฉื˜ ืžืึทื›ืŸ ืึท ืฉื ืขืœ ืจืขืคืจืขืฉืึทื‘ืœืข ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืคื•ืŸ ืงื™ื™ืคืœ ื˜ื™ืฉืŸ ืžื™ื˜ ืคึผืฉื•ื˜ ื“ื–ืฉื•ื™ื ืฅ ื•ื•ืึธืก ืึทืจื™ื™ึทื ื ืขืžืขืŸ ืึท ื›ื™ื™ืคืขืฅ ื˜ื™ืคึผ ื–ื™ื™ึทืœ ืื™ืŸ ื“ื™ SELECT ื“ืขืจืงืœืขืจื•ื ื’.

ืื•ื™ืš, ื“ืขืจ ื“ืขืจืคืจื™ืฉืŸ ืื•ืคึฟืŸ ืื™ืจ ืงืœื™ื™ึทื‘ืŸ ื•ื•ืขื˜ ื ื™ืฉื˜ ื–ื™ื™ืŸ ืึธืคึผื˜ื™ืžืึทืœ ืขืคืขืงื˜ื™ื•ื• ืื•ื™ื‘:

  • ื“ื™ ื“ื™ืคื™ื™ื ื™ื ื’ ืึธื ืคึฟืจืขื’ ื ื™ืฆื˜ ืึท ื•ื™ืกื•ื•ื™ื™ื ื™ืงืกื˜ ืคืึทืจื‘ื™ื ื“ืŸ ื•ื•ืึธืก ื‘ื™ื›ื™ื™ื•ื•ื– ื•ื•ื™ ืึท ื™ื ืขืจ ืคืึทืจื‘ื™ื ื“ืŸ. ืื•ื™ื‘ ื“ื™ ื“ื™ืคื™ื™ื ื™ื ื’ ืึธื ืคึฟืจืขื’ ื›ึผื•ืœืœ ืึทื–ืึท ืึท ืคืึทืจื‘ื™ื ื“ืŸ, ื‘ืึทื˜ืจืึทื›ื˜ืŸ ืจื™ืจื™ื™ื˜ื™ื ื’ ื“ื™ ื“ื™ืคื™ื™ื ื™ื ื’ ืึธื ืคึฟืจืขื’ ืฆื• ืึทื ื˜ื”ืึทืœื˜ืŸ ืึทืŸ ื™ื ืขืจ ืคืึทืจื‘ื™ื ื“ืŸ.
  • ื“ื™ SELECT ืจืฉื™ืžื” ืคื•ืŸ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ื›ึผื•ืœืœ ืื•ื™ืกื“ืจื•ืงืŸ ืื•ื™ืฃ ืฉืคืืœื˜ืŸ ืคื•ืŸ ืงื™ื™ืคืœ ื˜ื™ืฉืŸ.

5.3.8.6 ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื•ื™ืฃ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ ืื•ื™ืฃ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ ืึทื’ื’ืจืขื’ืึทื˜ืขืก

ื“ื™ืคื™ื™ื ื™ื ื’ ืคึฟืจืื’ืŸ ืคึฟืึทืจ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ ืึทื’ื’ืจืขื’ืึทืฅ ืึธื“ืขืจ ื“ื–ืฉื•ื™ื ืฅ ื”ืึธื‘ืŸ ื“ื™ ืคืืœื’ืขื ื“ืข ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื•ื™ืฃ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ:

ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ ืื™ื– ื’ืขืฉื˜ื™ืฆื˜ ืคึฟืึทืจ ื‘ื™ื™ื“ืข ON COMMIT ืื•ืŸ ON DEMAND ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ, ืึธื‘ืขืจ ื“ื™ ืคืืœื’ืขื ื“ืข ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืึทืคึผืœื™ื™ื–:

  • ืึทืœืข ื˜ื™ืฉืŸ ืื™ืŸ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื”ืึธื‘ืŸ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืœืึธื’ืก, ืื•ืŸ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืœืึธื’ืก ืžื•ื–ืŸ:
    • ืึทื ื˜ื”ืึทืœื˜ืŸ ืึทืœืข ืฉืคืืœื˜ืŸ ืคื•ืŸ ื“ื™ ื˜ื™ืฉ ืจืขืคืขืจืขื ืกื˜ ืื™ืŸ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’.
    • ืกืคึผืขืฆื™ืคื™ืฆื™ืจืŸ ืžื™ื˜ ROWID ืื•ืŸ INCLUDING NEW VALUES.
    • ืกืคึผืขืฆื™ืคื™ืฆื™ืจืŸ ื“ื™ SEQUENCE ืคึผื•ื ืงื˜ ืื•ื™ื‘ ื“ื™ ื˜ื™ืฉ ืื™ื– ื’ืขืจื™ื›ื˜ ืฆื• ื”ืึธื‘ืŸ ืึท ืžื™ืฉืŸ ืคื•ืŸ ื™ื ืกืขืจืฅ / ื“ื™ืจืขืงื˜ ืœืึธื•ื“ื–, ื“ื™ืœื™ืฅ ืื•ืŸ ื“ืขืจื”ื™ื™ึทื ื˜ื™ืงื•ื ื’ืขืŸ.

  • ื‘ืœื•ื™ื– SUM, COUNT, AVG, STDDEV, VARIANCE, MIN ืื•ืŸ MAX ื–ืขื ืขืŸ ื’ืขืฉื˜ื™ืฆื˜ ืคึฟืึทืจ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ.
  • COUNT(*) ืžื•ื–ืŸ ื–ื™ื™ึทืŸ ืกืคึผืขืกื™ืคื™ืขื“.
  • ืึทื’ื’ืจืขื’ืึทื˜ืข ืคืึทื ื’ืงืฉืึทื ื– ืžื•ื–ืŸ ืคึผืึทืกื™ืจืŸ ื‘ืœื•ื™ื– ื•ื•ื™ ื“ื™ ื•ื™ืกื•ื•ื™ื™ื ื™ืงืกื˜ ื˜ื™ื™ืœ ืคื•ืŸ ื“ื™ ืื•ื™ืกื“ืจื•ืง. ืึทื– ืื™ื–, ืึทื’ื’ืจืขื’ืึทืฅ ืึทื–ืึท ื•ื•ื™ AVG(AVG(x)) or AVG(x)+ AVG(x) ื–ืขื ืขืŸ ื ื™ืฉื˜ ืขืจืœื•ื™ื‘ื˜.
  • ืคึฟืึทืจ ื™ืขื“ืขืจ ื’ืขืžื™ื™ื ื–ืึทื ืึทื–ืึท ื•ื•ื™ AVG(expr), ื“ื™ ืงืึธืจืึทืกืคึผืึทื ื“ื™ื ื’ COUNT(expr) ืžื•ื–ืŸ ื–ื™ื™ืŸ ืคืึธืจืฉื˜ืขืœืŸ. ืึธืจืึทืงืœืข ืจืขืงืึทืžืขื ื“ื– ืึทื– SUM(expr) ืกืคึผืขืฆื™ืคื™ืฆื™ืจื˜ ื•ื•ืขืจืŸ.
  • If VARIANCE(expr) or STDDEV(expr) ืื™ื– ืกืคึผืขืกื™ืคื™ืขื“, COUNT(expr) ืื•ืŸ SUM(expr) ืžื•ื–ืŸ ื–ื™ื™ึทืŸ ืกืคึผืขืกื™ืคื™ืขื“. ืึธืจืึทืงืœืข ืจืขืงืึทืžืขื ื“ื– ืึทื– SUM(expr *expr) ืกืคึผืขืฆื™ืคื™ืฆื™ืจื˜ ื•ื•ืขืจืŸ.
  • ื“ื™ SELECT ื–ื™ื™ึทืœ ืื™ืŸ ื“ื™ ื“ื™ืคื™ื™ื ื™ื ื’ ืึธื ืคึฟืจืขื’ ืงืขืŸ ื ื™ืฉื˜ ื–ื™ื™ืŸ ืึท ืงืึธืžืคึผืœืขืงืก ืื•ื™ืกื“ืจื•ืง ืžื™ื˜ ืฉืคืืœื˜ืŸ ืคื•ืŸ ืงื™ื™ืคืœ ื‘ืึทื–ืข ื˜ื™ืฉืŸ. ื ืžืขื’ืœืขืš ื•ื•ืึธืจืงืึทืจืึธื•ื ื“ ืฆื• ื“ืขื ืื™ื– ืฆื• ื ื•ืฆืŸ ืึท ื ืขืกื˜ืขื“ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’.
  • ื“ื™ SELECT ืจืฉื™ืžื” ืžื•ื–ืŸ ืึทื ื˜ื”ืึทืœื˜ืŸ ืึทืœืข GROUP BY ืฉืคืืœื˜ืŸ.
  • ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืื™ื– ื ื™ืฉื˜ ื‘ืื–ื™ืจื˜ ืื•ื™ืฃ ืื™ื™ืŸ ืึธื“ืขืจ ืžืขืจ ื•ื•ื™ื™ึทื˜ ื˜ื™ืฉืŸ.
  • ืื•ื™ื‘ ืื™ืจ ื ื•ืฆืŸ ืึท CHAR ื“ืึทื˜ืŸ ื˜ื™ืคึผ ืื™ืŸ ื“ื™ ืคื™ืœื˜ืขืจ ืฉืคืืœื˜ืŸ ืคื•ืŸ ืึท ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืงืœืึธืฅ, ื“ื™ ื›ืึทืจืึทืงื˜ืขืจ ืฉื˜ืขืœื˜ ืคื•ืŸ ื“ื™ ื‘ืขืœ ืคึผืœืึทืฅ ืื•ืŸ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื–ื™ื™ืŸ ื“ื™ ื–ืขืœื‘ืข.
  • ืื•ื™ื‘ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ื”ืื˜ ืื™ื™ื ืขืจ ืคื•ืŸ ื“ื™ ืคืืœื’ืขื ื“ืข, ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ ืื™ื– ื’ืขืฉื˜ื™ืฆื˜ ื‘ืœื•ื™ื– ืื•ื™ืฃ ืงืึทื ื•ื•ืขื ืฉืึทื ืึทืœ DML ื™ื ืกืขืจืฅ ืื•ืŸ ื“ื™ืจืขืงื˜ ืœืึธื•ื“ื–.
    • ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ MIN or MAX ืึทื’ื’ืจืขื’ืึทืฅ
    • ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ื•ื•ืึธืก ื”ืึธื‘ืŸ SUM(expr) ืึธื‘ืขืจ ื ื™ื˜ COUNT(expr)
    • ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืึธืŸ COUNT(*)

    ืึทื–ืึท ืึท ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืื™ื– ื’ืขืจื•ืคืŸ ืึทืŸ ืึทืจื™ื™ึทื ืœื™ื™ื’ืŸ-ื‘ืœื•ื™ื– ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’.

  • ื ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื™ื˜ MAX or MIN ืื™ื– ืฉื ืขืœ ืจื™ืคืจืขืฉืึทื‘ืึทืœ ื ืึธืš ื•ื™ืกืžืขืงืŸ ืึธื“ืขืจ ื’ืขืžื™ืฉื˜ DML ืกื˜ื™ื™ื˜ืžืึทื ืฅ ืื•ื™ื‘ ืขืก ืื™ื– ื ื™ืฉื˜ ืึท WHERE ืคึผืึทืจืึทื’ืจืึทืฃ.
    ื“ื™ ืžืึทืงืก / ืžื™ืŸ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ ื ืึธืš ื•ื™ืกืžืขืงืŸ ืึธื“ืขืจ ื’ืขืžื™ืฉื˜ DML ื˜ื•ื˜ ื ื™ืฉื˜ ื”ืึธื‘ืŸ ื“ื™ ื–ืขืœื‘ืข ื ืึทื˜ื•ืจ ื•ื•ื™ ื“ื™ ืึทืจื™ื™ึทื ืœื™ื™ื’ืŸ-ื‘ืœื•ื™ื– ืคืึทืœ. ืขืก ื“ื™ืœื™ืฅ ืื•ืŸ ืจื™ืงืึทืžืคึผื™ื•ืฅ ื“ื™ ืžืึทืงืกื™ืžื•ื / ืžื™ืŸ ื•ื•ืึทืœื•ืขืก ืคึฟืึทืจ ื“ื™ ืึทืคืขืงื˜ืึทื“ ื’ืจื•ืคึผืขืก. ืื™ืจ ื“ืึทืจืคึฟืŸ ืฆื• ื–ื™ื™ืŸ ืึทื•ื•ืขืจ ืคื•ืŸ ื–ื™ื™ึทืŸ ืคืึธืจืฉื˜ืขืœื•ื ื’ ืคึผืจืึทืœ.
  • ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ ื’ืขื”ื™ื™ืกืŸ ืงื•ืงืŸ ืึธื“ืขืจ ืกืึทื‘ืงื•ื•ืขืจื™ื– ืื™ืŸ ื“ื™ FROM ืคึผื•ื ืงื˜ ืงืขื ืขืŸ ื–ื™ื™ืŸ ื’ืขืฉื•ื•ื™ื ื“ ื“ืขืจืงื•ื•ื™ืงื˜ ืื•ื™ื‘ ื“ื™ ืงื•ืงืŸ ืงืขื ืขืŸ ื–ื™ื™ืŸ ื’ืึธืจ ืžืขืจื“ื–ืฉื“. ืคึฟืึทืจ ืื™ื ืคึฟืึธืจืžืึทืฆื™ืข ืื•ื™ืฃ ื•ื•ืึธืก ืงื•ืงืŸ ื•ื•ืขื˜ ืฆื•ื ื•ื™ืคื’ื™ืกืŸ, ื–ืขืŸ ืึธืจืึทืงืœืข ื“ืึทื˜ืึทื‘ืึทืกืข ืกืงืœ ืฉืคึผืจืึทืš ืจืขืคืขืจืขื ืฅ.
  • ืื•ื™ื‘ ืขืก ื–ืขื ืขืŸ ืงื™ื™ืŸ ื•ื™ืกื•ื•ื™ื™ื ื™ืงืกื˜ ื“ื–ืฉื•ื™ื ืฅ, ืื™ืจ ืงืขืŸ ื”ืึธื‘ืŸ ืึทืจื‘ื™ื˜ืจืึทืจื™ืฉ ืกืึทืœืขืงืฉืึทื ื– ืื•ืŸ ื“ื–ืฉื•ื™ื ืฅ ืื™ืŸ ื“ื™ WHERE ืคึผืึทืจืึทื’ืจืึทืฃ.
  • ืžืึทื˜ืขืจื™ืึทืœื™ื–ืขื“ ื’ืขืžื™ื™ื ื–ืึทื ืงื•ืงืŸ ืžื™ื˜ ื•ื™ืกื•ื•ื™ื™ื ื™ืงืกื˜ ื“ื–ืฉื•ื™ื ืฅ ื–ืขื ืขืŸ ืฉื ืขืœ ืจื™ืคืจืขืฉืึทื‘ืึทืœ ื ืึธืš ืงืึทื ื•ื•ืขื ืฉืึทื ืึทืœ ื“ืžืœ ืื•ืŸ ื“ื™ืจืขืงื˜ ืœืึธื•ื“ื–, ืฆื•ื’ืขืฉื˜ืขืœื˜ ื‘ืœื•ื™ื– ื“ื™ ื•ื™ืกื•ื•ื™ื™ื ื™ืงืกื˜ ื˜ื™ืฉ ืื™ื– ืžืึทื“ืึทืคื™ื™ื“. ืื•ื™ืš, ื™ื™ื ืฆื™ืง ืงืึทื ืกื˜ืจื™ื™ื ืฅ ืžื•ื–ืŸ ืขืงืกื™ืกื˜ื™ืจืŸ ืื•ื™ืฃ ื“ื™ ืคืึทืจื‘ื™ื ื“ืŸ ืฉืคืืœื˜ืŸ ืคื•ืŸ ื“ื™ ื™ื ืขืจ ืคืึทืจื‘ื™ื ื“ืŸ ื˜ื™ืฉ. ืื•ื™ื‘ ืขืก ื–ืขื ืขืŸ ื•ื™ืกื•ื•ื™ื™ื ื™ืงืกื˜ ื“ื–ืฉื•ื™ื ืฅ, ืึทืœืข ื“ื™ ื“ื–ืฉื•ื™ื ืฅ ืžื•ื–ืŸ ื–ื™ื™ืŸ ืคืืจื‘ื•ื ื“ืŸ ื“ื•ืจืš ANDs ืื•ืŸ ืžื•ื–ืŸ ื ื•ืฆืŸ ื“ื™ ื™ืงื•ื•ืึทืœืึทื˜ื™ (=) ืึธืคึผืขืจืึทื˜ืึธืจ.
  • ืคึฟืึทืจ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ CUBE, ROLLUP, ื’ืจื•ืคึผื™ื ื’ ืฉื˜ืขืœื˜, ืึธื“ืขืจ ืงืึทื ืงืึทื˜ืึทื ื™ื™ืฉืึทืŸ ืคื•ืŸ ื–ื™ื™, ื“ื™ ืคืืœื’ืขื ื“ืข ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืึทืคึผืœื™ื™ื–:
    • ื“ื™ SELECT ืจืฉื™ืžื” ื–ืึธืœ ืึทื ื˜ื”ืึทืœื˜ืŸ ื’ืจื•ืคึผื™ื ื’ ื“ื™ืกื˜ื™ื ื’ื’ื•ื•ื™ืฉืขืจื– ื•ื•ืึธืก ืงืขื ืขืŸ ื–ื™ื™ืŸ ืึท GROUPING_ID ืคื•ื ืงืฆื™ืึธื ื™ืจืŸ ืื•ื™ืฃ ืึทืœืข GROUP BY ืื•ื™ืกื“ืจื•ืงืŸ ืึธื“ืขืจ GROUPING ืคืึทื ื’ืงืฉืึทื ื– ืื™ื™ื ืขืจ ืคึฟืึทืจ ื™ืขื“ืขืจ GROUP BY ืื•ื™ืกื“ืจื•ืง. ืคึฟืึทืจ ื‘ื™ื™ึทืฉืคึผื™ืœ, ืื•ื™ื‘ ื“ื™ GROUP BY ืคึผื•ื ืงื˜ ืคื•ืŸ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืื™ื– "GROUP BY CUBE(a, b)", ื“ืขืžืึธืœื˜ ื“ืขืจ SELECT ืจืฉื™ืžื” ื–ืึธืœ ืึทื ื˜ื”ืึทืœื˜ืŸ ืึธื“ืขืจ "GROUPING_ID(a, b)ยป ืึธื“ืขืจ ยซGROUPING(a) AND GROUPING(b)ยป ืคึฟืึทืจ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืฆื• ื–ื™ื™ืŸ ืฉื ืขืœ ืจื™ืคืจืขืฉืึทื‘ืึทืœ.
    • GROUP BY ื–ืึธืœ ื ื™ืฉื˜ ืจืขื–ื•ืœื˜ืึทื˜ ืื™ืŸ ืงื™ื™ืŸ ื“ื•ืคึผืœื™ืงืึทื˜ ื’ืจื•ืคึผื™ื ื’. ืœืžืฉืœ, "GROUP BY a, ROLLUP(a, b)"ืื™ื– ื ื™ืฉื˜ ืฉื ืขืœ ืจื™ืคืจืขืฉืึทื‘ืึทืœ ื•ื•ื™ื™ึทืœ ืขืก ืจืขื–ื•ืœื˜ืื˜ืŸ ืื™ืŸ ื“ื•ืคึผืœื™ืงืึทื˜ ื’ืจื•ืคึผืขืก"(a), (a, b), AND (a)".

5.3.8.7 ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื•ื™ืฃ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ ืื•ื™ืฃ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ UNION ALL

ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ ื“ื™ UNION ALL ืฉื˜ืขืœืŸ ืึธืคึผืขืจืึทื˜ืึธืจ ืฉื˜ื™ืฆืŸ ื“ื™ REFRESH FAST ืึธืคึผืฆื™ืข ืื•ื™ื‘ ื“ื™ ืคืืœื’ืขื ื“ืข ื˜ื ืึธื™ื ื–ืขื ืขืŸ ืฆื•ืคึฟืจื™ื“ืŸ:

  • ื“ื™ ื“ื™ืคื™ื™ื ื™ื ื’ ืึธื ืคึฟืจืขื’ ืžื•ื–ืŸ ื”ืึธื‘ืŸ ื“ื™ UNION ALL ืึธืคึผืขืจืึทื˜ืึธืจ ืื™ืŸ ื“ืขืจ ืฉืคึผื™ืฅ ืžื“ืจื’ื”.

    ื“ื™ UNION ALL ืึธืคึผืขืจืึทื˜ืึธืจ ืงืขื ืขืŸ ื ื™ื˜ ื–ื™ื™ืŸ ืขืžื‘ืขื“ื™ื“ ื™ืŸ ืึท ืกืึทื‘ืงื•ื•ืขืจื™, ืžื™ื˜ ืื™ื™ืŸ ื•ื™ืกื ืขื: ื“ื™ UNION ALL ืงืขื ืขืŸ ื–ื™ื™ืŸ ืื™ืŸ ืึท ืกืึทื‘ืงื•ื•ืขืจื™ ืื™ืŸ ื“ื™ FROM ืคึผื•ื ืงื˜ ืื•ื™ื‘ ื“ื™ ื“ื™ืคื™ื™ื ื™ื ื’ ืึธื ืคึฟืจืขื’ ืื™ื– ืคื•ืŸ ื“ื™ ืคืึธืจืขื SELECT * FROM (View ืึธื“ืขืจ ืกืึทื‘ืงื•ื•ืขืจื™ ืžื™ื˜ UNION ALL) ื•ื•ื™ ืื™ืŸ ื“ื™ ืคืืœื’ืขื ื“ืข ื‘ื™ื™ึทืฉืคึผื™ืœ:

    CREATE VIEW view_with_unionall AS (SELECT c.rowid crid, c.cust_id, 2 umarker FROM ืงืึทืกื˜ืึทืžืขืจื– c WHERE c.cust_last_name = 'Smith' UNION ALL SELECT c.rowid crid, c.cust_id, 3 umarker FROM ืงืึทืกื˜ืึทืžืขืจื– c WHERE c.cust_last_name = 'ื“ื–ืฉื•ื ื–'); ืฉืึทืคึฟืŸ ืžืึทื˜ืขืจื™ืึทืœื™ื–ืขื“ ืžื™ื™ื ื•ื ื’ unionall_inside_view_mv ื“ืขืจืคืจื™ืฉืŸ ืฉื ืขืœ ืื•ื™ืฃ ืคืึธื“ืขืจื•ื ื’ ื•ื•ื™ ืกืขืœืขืงื˜ื™ืจืŸ * ืคึฟื•ืŸ view_with_unionall;

    ื‘ืึทืžืขืจืงื•ื ื’ ืึทื– ื“ื™ ืžื™ื™ื ื•ื ื’ view_with_unionall ืกืึทื˜ื™ืกืคื™ื™ื– ื“ื™ ื‘ืื“ืขืจืคืขื ื™ืฉืŸ ืคึฟืึทืจ ืฉื ืขืœ ื“ืขืจืคืจื™ืฉืŸ.

  • ื™ืขื“ืขืจ ืึธื ืคึฟืจืขื’ ื‘ืœืึธืง ืื™ืŸ ื“ื™ UNION ALL ืึธื ืคึฟืจืขื’ ืžื•ื–ืŸ ื‘ืึทืคืจื™ื“ื™ืงืŸ ื“ื™ ืจืขืงื•ื•ื™ืจืขืžืขื ืฅ ืคื•ืŸ ืึท ืฉื ืขืœ ืจืขืคืจืขืฉืึทื‘ืœืข ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื™ื˜ ืึทื’ื’ืจืขื’ืึทืฅ ืึธื“ืขืจ ืึท ืฉื ืขืœ ืจืขืคืจืขืฉืึทื‘ืœืข ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื™ื˜ ื“ื–ืฉื•ื™ื ืฅ.

    ื“ื™ ืฆื•ื ืขืžืขืŸ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืœืึธื’ืก ืžื•ื–ืŸ ื–ื™ื™ืŸ ื‘ืืฉืืคืŸ ืื•ื™ืฃ ื“ื™ ื˜ื™ืฉืŸ ื•ื•ื™ ืคืืจืœืื ื’ื˜ ืคึฟืึทืจ ื“ื™ ืงืึธืจืึทืกืคึผืึทื ื“ื™ื ื’ ื˜ื™ืคึผ ืคื•ืŸ ืฉื ืขืœ ืจื™ืคืจืขืฉืึทื‘ืึทืœ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’.
    ื‘ืึทืžืขืจืงื•ื ื’ ืึทื– ื“ื™ ืึธืจืึทืงืœืข ื“ืึทื˜ืึทื‘ืึทืกืข ืื•ื™ืš ืึทืœืึทื•ื– ื“ื™ ืกืคึผืขืฆื™ืขืœ ืคืึทืœ ืคื•ืŸ ืึท ืื™ื™ืŸ ื˜ื™ืฉ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื™ื˜ ื“ื–ืฉื•ื™ื ืฅ ื‘ืœื•ื™ื– ืฆื•ื’ืขืฉื˜ืขืœื˜ ื“ื™ ROWID ื–ื™ื™ึทืœ ืื™ื– ืึทืจื™ื™ึทื ื’ืขืจืขื›ื ื˜ ืื™ืŸ ื“ื™ SELECT ืจืฉื™ืžื” ืื•ืŸ ืื™ืŸ ื“ื™ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืง ืงืœืึธืฅ. ื“ืึธืก ืื™ื– ื’ืขื•ื•ื™ื–ืŸ ืื™ืŸ ื“ื™ ื“ื™ืคื™ื™ื ื™ื ื’ ืึธื ืคึฟืจืขื’ ืคื•ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’ view_with_unionall.

  • ื“ื™ SELECT ืจืฉื™ืžื” ืคื•ืŸ ื™ืขื“ืขืจ ืึธื ืคึฟืจืขื’ ืžื•ื–ืŸ ืึทืจื™ื™ึทื ื ืขืžืขืŸ ืึท UNION ALL ืžืึทืจืงืขืจ, ืื•ืŸ ื“ื™ UNION ALL ื–ื™ื™ึทืœ ืžื•ื–ืŸ ื”ืึธื‘ืŸ ืึท ื‘ื•ื™ืœืขื˜ ืงืขืกื™ื™ื“ืขืจื“ื™ืง ื ื•ืžืขืจื™ืง ืึธื“ืขืจ ืฉื˜ืจื™ืงืœ ื•ื•ืขืจื˜ ืื™ืŸ ื™ืขื“ืขืจ UNION ALL ืฆื•ื•ื™ื™ึทื’. ื•ื•ื™ื™ึทื˜ืขืจ, ื“ื™ ืžืึทืจืงืขืจ ื–ื™ื™ึทืœ ืžื•ื–ืŸ ื“ืขืจืฉื™ื™ึทื ืขืŸ ืื™ืŸ ื“ืขืจ ื–ืขืœื‘ื™ืงืขืจ ืึธืจื“ืึทื ืึทืœ ืฉื˜ืขืœืข ืื™ืŸ ื“ื™ SELECT ืจืฉื™ืžื” ืคื•ืŸ ื™ืขื“ืขืจ ืึธื ืคึฟืจืขื’ ื‘ืœืึธืง. ื–ืขืŸ "UNION ALL ืžืึทืจืงืขืจ ืื•ืŸ ืึธื ืคืจืขื’ ืจื™ืจื™ื™ื˜ยป ืคึฟืึทืจ ืžืขืจ ืื™ื ืคึฟืึธืจืžืึทืฆื™ืข ื•ื•ืขื’ืŸ UNION ALL ืžืึทืจืงืขืจืก.
  • ืขื˜ืœืขื›ืข ืคึฟืขื™ึดืงื™ื™ื˜ืŸ ืึทื–ืึท ื•ื•ื™ ื•ื™ืกื•ื•ื™ื™ื ื™ืงืกื˜ ื“ื–ืฉื•ื™ื ืฅ, ืึทืจื™ื™ึทื ืœื™ื™ื’ืŸ-ื‘ืœื•ื™ื– ื’ืขืžื™ื™ื ื–ืึทื ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืงื•ื•ื™ืจื™ื– ืื•ืŸ ื•ื•ื™ื™ึทื˜ ื˜ื™ืฉืŸ ื–ืขื ืขืŸ ื ื™ืฉื˜ ื’ืขืฉื˜ื™ืฆื˜ ืคึฟืึทืจ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ืžื™ื˜ UNION ALL. ื‘ืึทืžืขืจืงื•ื ื’, ืึธื‘ืขืจ, ืึทื– ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืงื•ืงืŸ ื’ืขื ื™ืฆื˜ ืื™ืŸ ืจืขืคึผืœืึทืงื™ื™ืฉืึทืŸ, ื•ื•ืึธืก ื˜ืึธืŸ ื ื™ื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ื“ื–ืฉื•ื™ื ืฅ ืึธื“ืขืจ ืึทื’ื’ืจืขื’ืึทืฅ, ืงืขื ืขืŸ ื–ื™ื™ืŸ ืฉื ืขืœ ื“ืขืจืงื•ื•ื™ืงื˜ ื•ื•ืขืŸ UNION ALL ืึธื“ืขืจ ื•ื•ื™ื™ึทื˜ ื˜ื™ืฉืŸ ื–ืขื ืขืŸ ื’ืขื ื™ืฆื˜.
  • ื“ื™ ืงืึทืžืคึผืึทื˜ืึทื‘ื™ืœืึทื˜ื™ ื™ื ื™ื˜ื™ืึทืœื™ื–ืึทื˜ื™ืึธืŸ ืคึผืึทืจืึทืžืขื˜ืขืจ ืžื•ื–ืŸ ื–ื™ื™ืŸ ืฉื˜ืขืœืŸ ืฆื• 9.2.0 ืึธื“ืขืจ ื”ืขื›ืขืจ ืฆื• ืฉืึทืคึฟืŸ ืึท ืฉื ืขืœ ืจื™ืคืจืขืฉืึทื‘ืึทืœ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืžื™ื™ื ื•ื ื’ ืžื™ื˜ UNION ALL.

ืื™ืš ื˜ืึธืŸ ื ื™ืฉื˜ ื•ื•ืขืœืŸ ืฆื• ื‘ืึทืœื™ื™ื“ื™ืงืŸ ืึธืจืึทืงืœืข ืคืึทื ืก, ืึธื‘ืขืจ ืื•ื™ื‘ ืžืฉืคื˜ืŸ ืœื•ื™ื˜ ื–ื™ื™ืขืจ ืจืฉื™ืžื” ืคื•ืŸ ืจื™ืกื˜ืจื™ืงืฉืึทื ื–, ืขืก ืžื™ื™ื ื˜ ืึทื– ื“ืขืจ ืžืขืงืึทื ื™ื–ืึทื ืื™ื– ื’ืขื•ื•ืขืŸ ื’ืขืฉืจื™ื‘ืŸ ื ื™ืฉื˜ ืื™ืŸ ื“ื™ ืึทืœื’ืขืžื™ื™ื ืข ืคืึทืœ, ื ื™ืฆืŸ ืขื˜ืœืขื›ืข ืžื™ืŸ ืคื•ืŸ ืžืึธื“ืขืœ, ืึธื‘ืขืจ ื“ื•ืจืš ื˜ื•ื™ื–ื ื˜ืขืจ ืคื•ืŸ ื™ื ื“ื™ืึทื ืก, ื•ื•ื• ืึทืœืขืžืขืŸ ืื™ื– ื’ืขื•ื•ืขืŸ ื’ืขื’ืขื‘ืŸ ื“ื™ ื’ืขืœืขื’ื ื”ื™ื™ื˜ ืฆื• ืฉืจื™ื™ื‘ื˜ ื–ื™ื™ืขืจ ืื™ื™ื’ืขื ืขืจ ืฆื•ื•ื™ื™ื’, ืื•ืŸ ื™ืขื“ืขืจ ืคื•ืŸ ื–ื™ื™ ื”ืื˜ ื’ืขื˜ืืŸ ื•ื•ืืก ืขืจ ื”ืื˜ ื’ืขืงืขื ื˜. ื ื™ืฆืŸ ื“ืขื ืžืขืงืึทื ื™ื–ืึทื ืคึฟืึทืจ ืคืึทืงื˜ื™ืฉ ืœืึธื’ื™ืง ืื™ื– ื•ื•ื™ ื’ื™ื™ืŸ ื“ื•ืจืš ืึท ืžื™ื™ื ืคื™ืœื“. ืื™ืจ ืงืขื ืขืŸ ื‘ืึทืงื•ืžืขืŸ ืึท ืžื™ื™ึทืŸ ืื™ืŸ ืงื™ื™ืŸ ืฆื™ื™ื˜ ื“ื•ืจืš ื”ื™ื˜ื˜ื™ื ื’ ืื™ื™ื ืขืจ ืคื•ืŸ ื“ื™ ื ื™ื˜ ืงืœืึธืจ ื•ื•ื™ ื“ืขืจ ื˜ืึธื’ ืจื™ืกื˜ืจื™ืงืฉืึทื ื–. ื•ื•ื™ ืขืก ืึทืจื‘ืขื˜ ืื™ื– ืื•ื™ืš ืึท ื‘ืึทื–ื•ื ื“ืขืจ ืงืฉื™ื, ืึธื‘ืขืจ ืขืก ืื™ื– ื•ื•ื™ื™ึทื˜ืขืจ ืคื•ืŸ ื“ื™ ืคืึทืจื ืขื ืคื•ืŸ ื“ืขื ืึทืจื˜ื™ืงืœ.

ืžื™ืงืจืึธืกืึธืคื˜ ืกืงืœ ืกืขืจื•ื•ื™ืจืขืจ

ื ืึธืš ืจืขืงื•ื•ื™ืจืขืžืขื ืฅ

ืื™ืŸ ืึทื“ื™ืฉืึทืŸ ืฆื• ื“ื™ SET ืึธืคึผืฆื™ืขืก ืื•ืŸ ื“ื™ื˜ืขืจืžืึทื ื™ืกื˜ื™ืง ืคืึทื ื’ืงืฉืึทื ื– ืจืขืงื•ื•ื™ืจืขืžืขื ืฅ, ื“ื™ ืคืืœื’ืขื ื“ืข ืจืขืงื•ื•ื™ืจืขืžืขื ืฅ ืžื•ื–ืŸ ื–ื™ื™ืŸ ื‘ืื’ืขื’ื ื˜:

  • ื“ืขืจ ื‘ืึทื ื™ืฆืขืจ ื•ื•ืึธืก ืขืงืกืึทืงื™ื•ืฅ CREATE INDEX ืžื•ื–ืŸ ื–ื™ื™ืŸ ื“ื™ ื‘ืึทื–ื™ืฆืขืจ ืคื•ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’.
  • ื•ื•ืขืŸ ืื™ืจ ืžืึทื›ืŸ ื“ืขื ืื™ื ื“ืขืงืก, ื“ื™ IGNORE_DUP_KEY ืึธืคึผืฆื™ืข ืžื•ื–ืŸ ื–ื™ื™ืŸ ืฉื˜ืขืœืŸ ืฆื• OFF (ื“ื™ ืคืขืœื™ืงื™ื™ึทื˜ ื‘ืึทืฉื˜ืขื˜ื™ืงืŸ).
  • ื˜ืึทื‘ืœืขืก ืžื•ื–ืŸ ื–ื™ื™ืŸ ืจืขืคืขืจืขื ืกื˜ ื“ื•ืจืš ืฆื•ื•ื™ื™-ื˜ื™ื™ืœ ื ืขืžืขืŸ, ืกื›ืขืžืข.ื˜ื™ืฉ ื ืึธืžืขืŸ ืื™ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’ ื“ืขืคึฟื™ื ื™ืฆื™ืข.
  • ื‘ืึทื ื™ืฆืขืจ-ื“ื™ืคื™ื™ื ื“ ืคืึทื ื’ืงืฉืึทื ื– ืจืขืคืขืจืขื ืกื˜ ืื™ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื–ื™ื™ืŸ ื‘ืืฉืืคืŸ ื“ื•ืจืš ื ื™ืฆืŸ ื“ื™ WITH SCHEMABINDING ืึธืคึผืฆื™ืข.
  • ืงื™ื™ืŸ ื‘ืึทื ื™ืฆืขืจ-ื“ื™ืคื™ื™ื ื“ ืคืึทื ื’ืงืฉืึทื ื– ืจืขืคืขืจืขื ืกื˜ ืื™ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื–ื™ื™ืŸ ืจืขืคืขืจืึทื ืกื˜ ื“ื•ืจืš ืฆื•ื•ื™ื™-ื˜ื™ื™ืœ ื ืขืžืขืŸ, ..
  • ื“ื™ ื“ืึทื˜ืŸ ืึทืงืกืขืก ืคืึทืจืžืึธื’ ืคื•ืŸ ืึท ื‘ืึทื ื™ืฆืขืจ-ื“ื™ืคื™ื™ื ื“ ืคึฟื•ื ืงืฆื™ืข ืžื•ื–ืŸ ื–ื™ื™ืŸ NO SQL, ืื•ืŸ ืคื•ื ื“ืจื•ื™ืกื ื“ื™ืง ืึทืงืกืขืก ืคืึทืจืžืึธื’ ืžื•ื–ืŸ ื–ื™ื™ืŸ NO.
  • ืคึผืจืึธืกื˜ ืฉืคึผืจืึทืš ืจื•ื ื˜ื™ืžืข (CLR) ืคืึทื ื’ืงืฉืึทื ื– ืงืขื ืขืŸ ื–ื™ื™ืŸ ื’ืขื•ื•ื™ื–ืŸ ืื™ืŸ ื“ื™ ืื•ื™ืกืงืœื™ื™ึทื‘ืŸ ืจืฉื™ืžื” ืคื•ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’, ืึธื‘ืขืจ ืงืขื ืขืŸ ื ื™ืฉื˜ ื–ื™ื™ืŸ ื˜ื™ื™ืœ ืคื•ืŸ ื“ื™ ื“ืขืคึฟื™ื ื™ืฆื™ืข ืคื•ืŸ โ€‹โ€‹ื“ื™ ืงืœืึทืกื˜ืขืจื“ ืื™ื ื“ืขืงืก ืฉืœื™ืกืœ. CLR ืคืึทื ื’ืงืฉืึทื ื– ืงืขื ืขืŸ ื ื™ืฉื˜ ื“ืขืจืฉื™ื™ึทื ืขืŸ ืื™ืŸ ื“ื™ WHERE ืคึผื•ื ืงื˜ ืคื•ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’ ืึธื“ืขืจ ื“ื™ ON ืคึผื•ื ืงื˜ ืคื•ืŸ ืึท JOIN ืึธืคึผืขืจืึทืฆื™ืข ืื™ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’.
  • CLR ืคืึทื ื’ืงืฉืึทื ื– ืื•ืŸ ืžืขื˜ื”ืึธื“ืก ืคื•ืŸ CLR ื‘ืึทื ื™ืฆืขืจ-ื“ื™ืคื™ื™ื ื“ ื˜ื™ื™ืคึผืก ื’ืขื ื™ืฆื˜ ืื™ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’ ื“ืขืคึฟื™ื ื™ืฆื™ืข ืžื•ื–ืŸ ื”ืึธื‘ืŸ ื“ื™ ืคึผืจืึธืคึผืขืจื˜ื™ืขืก ืฉื˜ืขืœืŸ ื•ื•ื™ ื’ืขื•ื•ื™ื–ืŸ ืื™ืŸ ื“ื™ ืคืืœื’ืขื ื“ืข ื˜ื™ืฉ.

    ืคืึทืจืžืึธื’
    ื˜ืึธืŸ

    ื“ืขื˜ืขืจืžื™ื ื™ืกื˜ื™ืฉ = ืืžืช
    ืžื•ื–ืŸ ื–ื™ื™ืŸ ื“ืขืจืงืœืขืจื˜ ื‘ืคื™ืจื•ืฉ ื•ื•ื™ ืึท ืึทื˜ืจื™ื‘ื™ื•ื˜ ืคื•ืŸ ื“ื™ Microsoft .NET Framework ืื•ืคึฟืŸ.

    ื’ืขื ื•ื™ = ืืžืช
    ืžื•ื–ืŸ ื–ื™ื™ืŸ ื“ืขืจืงืœืขืจื˜ ื‘ืคื™ืจื•ืฉ ื•ื•ื™ ืึท ืึทื˜ืจื™ื‘ื™ื•ื˜ ืคื•ืŸ ื“ื™. ื ืขืฅ ืคืจืึทืžืขื•ื•ืึธืจืง ืื•ืคึฟืŸ.

    ื“ืึทื˜ืŸ ืึทืงืกืขืก = ืงื™ื™ืŸ ืกืงืœ
    ื‘ืืฉืœืืกืŸ ื“ื•ืจืš ื‘ืึทืฉื˜ืขื˜ื™ืงืŸ ื“ืึทื˜ืึทืึทืงืกืขืกืก ืึทื˜ืจื™ื‘ื™ื•ื˜ ืฆื• DataAccessKind.None ืื•ืŸ SystemDataAccess ืึทื˜ืจื™ื‘ื™ื•ื˜ ืฆื• SystemDataAccessKind.None.

    ืคื•ื ื“ืจื•ื™ืกื ื“ื™ืง ืึทืงืกืขืก = ื ื™ื™ืŸ
    ื“ื™ ืคืึทืจืžืึธื’ ื“ื™ืคืึธืœืฅ ืฆื• ืงื™ื™ืŸ ืคึฟืึทืจ CLR ืจื•ื˜ื™ื ื–.

  • ื“ื™ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื–ื™ื™ืŸ ื‘ืืฉืืคืŸ ื“ื•ืจืš ื ื™ืฆืŸ ื“ื™ WITH SCHEMABINDING ืึธืคึผืฆื™ืข.
  • ื“ืขืจ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื“ืขืจืžืึธื ืขืŸ ื‘ืœื•ื™ื– ื‘ืึทื–ืข ื˜ื™ืฉืŸ ื•ื•ืึธืก ื–ืขื ืขืŸ ืื™ืŸ ื“ืขืจ ื–ืขืœื‘ื™ืงืขืจ ื“ืึทื˜ืึทื‘ื™ื™ืก ื•ื•ื™ ื“ื™ ืžื™ื™ื ื•ื ื’. ื“ื™ ืžื™ื™ื ื•ื ื’ ืงืขืŸ ื ื™ืฉื˜ ื“ืขืจืžืึธื ืขืŸ ืื ื“ืขืจืข ืงื•ืงืŸ.
  • ื“ื™ SELECT ื•ื™ืกื–ืึธื’ื•ื ื’ ืื™ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’ ื“ืขืคึฟื™ื ื™ืฆื™ืข ืžื•ื–ืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ื“ื™ ืคืืœื’ืขื ื“ืข Transact-SQL ืขืœืขืžืขื ื˜ืŸ:

    COUNT
    ROWSET ืคืึทื ื’ืงืฉืึทื ื– (OPENDATASOURCE, OPENQUERY, OPENROWSET, ืื•ืŸ OPENXML)
    OUTER ืœื™ื™ื’ื˜ ื–ื™ืš (LEFT, RIGHT, ืื“ืขืจ FULL)

    ื“ืขืจื™ื™ื•ื•ื“ ื˜ื™ืฉ (ื“ื™ืคื™ื™ื ื“ ื“ื•ืจืš ืกืคึผืขืฆื™ืคื™ืฆื™ืจืŸ ืึท SELECT ื“ืขืจืงืœืขืจื•ื ื’ ืื™ืŸ ื“ื™ FROM ืคึผื•ื ืงื˜)
    ื–ื™ืš-ื“ื–ืฉื™ื ืก
    ืกืคึผืขืฆื™ืคื™ืฆื™ืจืŸ ืฉืคืืœื˜ืŸ ื“ื•ืจืš ื ื™ืฆืŸ SELECT * or SELECT <table_name>.*

    DISTINCT
    STDEV, STDEVP, VAR, VARP, ืื“ืขืจ AVG
    ืคึผืจืึธืกื˜ ื˜ื™ืฉ ืื•ื™ืกื“ืจื•ืง (CTE)

    ืœืึธื–ื  ืฉื•ื•ื™ืžืขืŸ1, ื˜ืขืงืกื˜, ntext, ื‘ื™ืœื“, ืงืกืžืœ, ืื“ืขืจ ืคื™ืœืขืกื˜ืจื™ื ืฉืคืืœื˜ืŸ
    ืกื•ื‘ืงื•ื•ืขืจื™
    OVER ืคึผื•ื ืงื˜, ื•ื•ืึธืก ื›ื•ืœืœ ืจืึทื ื’ ืึธื“ืขืจ ื’ืขืžื™ื™ื ื–ืึทื ืคึฟืขื ืฆื˜ืขืจ ืคืึทื ื’ืงืฉืึทื ื–

    ื’ืึทื ืฅ ื˜ืขืงืกื˜ ืคึผืจืขื“ื™ืงืึทื˜ืขืก (CONTAINS, FREETEXT)
    SUM ืคึฟื•ื ืงืฆื™ืข ื•ื•ืึธืก ืจืขืคืขืจืขื ืฆืŸ ืึท ื ื•ืœืึทื‘ืœืข ืื•ื™ืกื“ืจื•ืง
    ORDER BY

    CLR ื‘ืึทื ื™ืฆืขืจ-ื“ื™ืคื™ื™ื ื“ ื’ืขืžื™ื™ื ื–ืึทื ืคึฟื•ื ืงืฆื™ืข
    TOP
    CUBE, ROLLUP, ืื“ืขืจ GROUPING SETS ืึธืคึผืขืจื™ื™ื˜ืขืจื–

    MIN, MAX
    UNION, EXCEPT, ืื“ืขืจ INTERSECT ืึธืคึผืขืจื™ื™ื˜ืขืจื–
    TABLESAMPLE

    ื˜ื™ืฉ ื•ื•ืขืจื™ืึทื‘ืึทืœื–
    OUTER APPLY or CROSS APPLY
    PIVOT, UNPIVOT

    ืฉื™ื˜ืขืจ ื–ื™ื™ึทืœ ืฉื˜ืขืœื˜
    ื™ื ืœื™ื ืข (TVF) ืึธื“ืขืจ ืžื•ืœื˜ื™-ืกื˜ืึทื˜ืขืžืขื ื˜ ื˜ื™ืฉ-ื•ื•ืึทืœื™ื•ื“ ืคืึทื ื’ืงืฉืึทื ื– (MSTVF)
    OFFSET

    CHECKSUM_AGG

    1 ื“ื™ ื™ื ื“ืขืงืกื˜ ืžื™ื™ื ื•ื ื’ ืงืขื ืขืŸ ืึทื ื˜ื”ืึทืœื˜ืŸ ืœืึธื–ื  ืฉื•ื•ื™ืžืขืŸ ืฉืคืืœื˜ืŸ; ืึธื‘ืขืจ, ืึทื–ืึท ืฉืคืืœื˜ืŸ ืงืขื ืขืŸ ื ื™ื˜ ื–ื™ื™ืŸ ืึทืจื™ื™ึทื ื’ืขืจืขื›ื ื˜ ืื™ืŸ ื“ื™ ืงืœืึทืกื˜ืขืจื“ ืื™ื ื“ืขืงืก ืฉืœื™ืกืœ.

  • If GROUP BY ืื™ื– ืคืึธืจืฉื˜ืขืœืŸ, ื“ื™ VIEW ื“ืขืคึฟื™ื ื™ืฆื™ืข ืžื•ื–ืŸ ืึทื ื˜ื”ืึทืœื˜ืŸ COUNT_BIG(*) ืื•ืŸ ื–ืึธืœ ื ื™ื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ HAVING. ื“ื™ GROUP BY ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ื–ืขื ืขืŸ ืึธื ื•ื•ืขื ื“ืœืขืš ื‘ืœื•ื™ื– ืฆื• ื“ื™ ื™ื ื“ืขืงืกื˜ ืžื™ื™ื ื•ื ื’ ื“ืขืคึฟื™ื ื™ืฆื™ืข. ื ืึธื ืคึฟืจืขื’ ืงืขื ืขืŸ ื ื•ืฆืŸ ืึทืŸ ื™ื ื“ืขืงืกื˜ ืžื™ื™ื ื•ื ื’ ืื™ืŸ ื–ื™ื™ืŸ ื“ื•ืจื›ืคื™ืจื•ื ื’ ืคึผืœืึทืŸ ืืคื™ืœื• ืื•ื™ื‘ ืขืก ื˜ื•ื˜ ื ื™ืฉื˜ ื‘ืึทืคืจื™ื“ื™ืงืŸ ื“ื™ GROUP BY ืจื™ืกื˜ืจื™ืงืฉืึทื ื–.
  • ืื•ื™ื‘ ื“ื™ ืžื™ื™ื ื•ื ื’ ื“ืขืคึฟื™ื ื™ืฆื™ืข ื›ึผื•ืœืœ ืึท GROUP BY ืคึผื•ื ืงื˜, ื“ืขืจ ืฉืœื™ืกืœ ืคื•ืŸ ื“ื™ ื™ื™ื ืฆื™ืง ืงืœืึทืกื˜ืขืจื“ ืื™ื ื“ืขืงืก ืงืขื ืขืŸ ื“ืขืจืžืึธื ืขืŸ ื‘ืœื•ื™ื– ื“ื™ ืฉืคืืœื˜ืŸ ืกืคึผืขืกื™ืคื™ืขื“ ืื™ืŸ ื“ื™ GROUP BY ืคึผืึทืจืึทื’ืจืึทืฃ.

ืขืก ืื™ื– ืงืœืึธืจ ื“ืึธ ืึทื– ื“ื™ ื™ื ื“ื™ืึทื ืก ื–ืขื ืขืŸ ื ื™ืฉื˜ ื™ื ื•ื•ืึทืœื•ื•ื“, ื•ื•ื™ื™ึทืœ ื–ื™ื™ ื‘ืึทืฉืœืึธืกืŸ ืฆื• ื˜ืึธืŸ ื“ืึธืก ืœื•ื™ื˜ ื“ื™ ืกื›ืขืžืข "ืžื™ืจ ื•ื•ืขืœืŸ ื˜ืึธืŸ ืงืœื™ื™ืŸ, ืึธื‘ืขืจ ื’ืขื–ื•ื ื˜." ืึทื– ืื™ื–, ื–ื™ื™ ื”ืึธื‘ืŸ ืžืขืจ ืžื™ื ืขืก ืื•ื™ืฃ ื“ืขื ืคืขืœื“, ืึธื‘ืขืจ ื–ื™ื™ืขืจ ืึธืจื˜ ืื™ื– ืžืขืจ ื˜ืจืึทื ืกืคึผืขืจืึทื ื˜. ื“ื™ ืžืขืจืกื˜ ื“ื™ืกืึทืคึผื•ื™ื ื™ื“ ื–ืึทืš ืื™ื– ื“ื™ ื‘ืึทื’ืจืขื ืขืฆื•ื ื’:

ื“ืขืจ ืžื™ื™ื ื•ื ื’ ืžื•ื–ืŸ ื“ืขืจืžืึธื ืขืŸ ื‘ืœื•ื™ื– ื‘ืึทื–ืข ื˜ื™ืฉืŸ ื•ื•ืึธืก ื–ืขื ืขืŸ ืื™ืŸ ื“ืขืจ ื–ืขืœื‘ื™ืงืขืจ ื“ืึทื˜ืึทื‘ื™ื™ืก ื•ื•ื™ ื“ื™ ืžื™ื™ื ื•ื ื’. ื“ื™ ืžื™ื™ื ื•ื ื’ ืงืขืŸ ื ื™ืฉื˜ ื“ืขืจืžืึธื ืขืŸ ืื ื“ืขืจืข ืงื•ืงืŸ.

ืื™ืŸ ืื•ื ื“ื–ืขืจ ื˜ืขืจืžื™ื ืึธืœืึธื’ื™ืข, ื“ืึธืก ืžื™ื˜ืœ ืึทื– ืึท ืคึฟื•ื ืงืฆื™ืข ืงืขืŸ ื ื™ืฉื˜ ืฆื•ื˜ืจื™ื˜ ืืŸ ืื ื“ืขืจ ืžืึทื˜ื™ืจื™ืึทืœื™ื™ื–ื“ ืคึฟื•ื ืงืฆื™ืข. ื“ืึธืก ืฉื ื™ื™ื“ื˜ ืึทืจืึธืคึผ ืึทืœืข ืื™ื“ืขืึธืœืึธื’ื™ืข ืื™ืŸ ื“ื™ ืงื ืึธืกืคึผ.
ืื•ื™ืš, ื“ื™ ื‘ืึทื’ืจืขื ืขืฆื•ื ื’ (ืื•ืŸ ื•ื•ื™ื™ึทื˜ืขืจ ืื™ืŸ ื“ืขื ื˜ืขืงืกื˜) ืจืึทื“ื•ืกืึทื– ื“ื™ ื ื•ืฆืŸ ืงืึทืกืขืก ื–ื™ื™ืขืจ:

ื“ื™ SELECT ื•ื™ืกื–ืึธื’ื•ื ื’ ืื™ืŸ ื“ื™ ืžื™ื™ื ื•ื ื’ ื“ืขืคึฟื™ื ื™ืฆื™ืข ืžื•ื–ืŸ ื ื™ืฉื˜ ืึทื ื˜ื”ืึทืœื˜ืŸ ื“ื™ ืคืืœื’ืขื ื“ืข Transact-SQL ืขืœืขืžืขื ื˜ืŸ:

COUNT
ROWSET ืคืึทื ื’ืงืฉืึทื ื– (OPENDATASOURCE, OPENQUERY, OPENROWSET, ืื•ืŸ OPENXML)
OUTER ืœื™ื™ื’ื˜ ื–ื™ืš (LEFT, RIGHT, ืื“ืขืจ FULL)

ื“ืขืจื™ื™ื•ื•ื“ ื˜ื™ืฉ (ื“ื™ืคื™ื™ื ื“ ื“ื•ืจืš ืกืคึผืขืฆื™ืคื™ืฆื™ืจืŸ ืึท SELECT ื“ืขืจืงืœืขืจื•ื ื’ ืื™ืŸ ื“ื™ FROM ืคึผื•ื ืงื˜)
ื–ื™ืš-ื“ื–ืฉื™ื ืก
ืกืคึผืขืฆื™ืคื™ืฆื™ืจืŸ ืฉืคืืœื˜ืŸ ื“ื•ืจืš ื ื™ืฆืŸ SELECT * or SELECT <table_name>.*

DISTINCT
STDEV, STDEVP, VAR, VARP, ืื“ืขืจ AVG
ืคึผืจืึธืกื˜ ื˜ื™ืฉ ืื•ื™ืกื“ืจื•ืง (CTE)

ืœืึธื–ื  ืฉื•ื•ื™ืžืขืŸ1, ื˜ืขืงืกื˜, ntext, ื‘ื™ืœื“, ืงืกืžืœ, ืื“ืขืจ ืคื™ืœืขืกื˜ืจื™ื ืฉืคืืœื˜ืŸ
ืกื•ื‘ืงื•ื•ืขืจื™
OVER ืคึผื•ื ืงื˜, ื•ื•ืึธืก ื›ื•ืœืœ ืจืึทื ื’ ืึธื“ืขืจ ื’ืขืžื™ื™ื ื–ืึทื ืคึฟืขื ืฆื˜ืขืจ ืคืึทื ื’ืงืฉืึทื ื–

ื’ืึทื ืฅ ื˜ืขืงืกื˜ ืคึผืจืขื“ื™ืงืึทื˜ืขืก (CONTAINS, FREETEXT)
SUM ืคึฟื•ื ืงืฆื™ืข ื•ื•ืึธืก ืจืขืคืขืจืขื ืฆืŸ ืึท ื ื•ืœืึทื‘ืœืข ืื•ื™ืกื“ืจื•ืง
ORDER BY

CLR ื‘ืึทื ื™ืฆืขืจ-ื“ื™ืคื™ื™ื ื“ ื’ืขืžื™ื™ื ื–ืึทื ืคึฟื•ื ืงืฆื™ืข
TOP
CUBE, ROLLUP, ืื“ืขืจ GROUPING SETS ืึธืคึผืขืจื™ื™ื˜ืขืจื–

MIN, MAX
UNION, EXCEPT, ืื“ืขืจ INTERSECT ืึธืคึผืขืจื™ื™ื˜ืขืจื–
TABLESAMPLE

ื˜ื™ืฉ ื•ื•ืขืจื™ืึทื‘ืึทืœื–
OUTER APPLY or CROSS APPLY
PIVOT, UNPIVOT

ืฉื™ื˜ืขืจ ื–ื™ื™ึทืœ ืฉื˜ืขืœื˜
ื™ื ืœื™ื ืข (TVF) ืึธื“ืขืจ ืžื•ืœื˜ื™-ืกื˜ืึทื˜ืขืžืขื ื˜ ื˜ื™ืฉ-ื•ื•ืึทืœื™ื•ื“ ืคืึทื ื’ืงืฉืึทื ื– (MSTVF)
OFFSET

CHECKSUM_AGG

ื•ื™ืกื•ื•ื™ื™ื ื™ืงืกื˜ ื“ื–ืฉืึธื™ื ืก, ื™ื•ื ื™ืึทืŸ, ืกื“ืจ ื“ื•ืจืš ืื•ืŸ ืื ื“ืขืจืข ื–ืขื ืขืŸ ืคึผืจืึธื•ื›ื™ื‘ืึทื˜ืึทื“. ืขืก ืงืขืŸ ื”ืึธื‘ืŸ ื’ืขื•ื•ืขืŸ ื’ืจื™ื ื’ืขืจ ืฆื• ืกืคึผืขืฆื™ืคื™ืฆื™ืจืŸ ื•ื•ืึธืก ืงืขืŸ ื–ื™ื™ืŸ ื’ืขื•ื•ื™ื™ื ื˜ ื•ื•ื™ ื•ื•ืึธืก ืงืขืŸ ื ื™ืฉื˜ ื–ื™ื™ืŸ ื’ืขื•ื•ื™ื™ื ื˜. ื“ื™ ืจืฉื™ืžื” ื•ื•ืึธืœื˜ ืžื™ืกื˜ืึธืžืข ื–ื™ื™ืŸ ืคื™ืœ ืงืœืขื ืขืจืขืจ.

ืฆื• ืกืึทืžืขืจื™ื™ื–: ืึท ืจื™ื–ื™ืง ื’ืึทื ื’ ืคื•ืŸ ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื™ืŸ ื™ืขื“ืขืจ (ืœืึธื–ืŸ ืก ื˜ืึธืŸ ื’ืขืฉืขืคื˜) DBMS ื•ื•ืก ื’ืึธืจื ื™ื˜ (ืžื™ื˜ ื“ื™ ื•ื™ืกื ืขื ืคื•ืŸ ืื™ื™ืŸ ืœืึทื“ื–ืฉื™ืงืึทืœ, ื ื™ื˜ ื˜ืขื›ื ื™ืฉ) ืื™ืŸ LGPL ื˜ืขื›ื ืึธืœืึธื’ื™ืข. ืึธื‘ืขืจ, ืขืก ื–ืึธืœ ื–ื™ื™ืŸ ืื ื’ืขื•ื•ื™ื–ืŸ ืึทื– ื™ืžืคึผืœืึทืžืขื ื™ื ื’ ื“ืขื ืžืขืงืึทื ื™ื–ืึทื ืื™ืŸ ืจื™ืœื™ื™ืฉืึทื ืึทืœ ืœืึธื’ื™ืง ืื™ื– ืึท ื‘ื™ืกืœ ืžืขืจ ืฉื•ื•ืขืจ ื•ื•ื™ ืื™ืŸ ื“ื™ ื“ื™ืกืงืจื™ื™ื‘ื“ ืคืึทื ื’ืงืฉืึทื ืึทืœ ืœืึธื’ื™ืง.

ื™ืžืคึผืœืขืžืขื ื˜ืึทื˜ื™ืึธืŸ

ื•ื•ื™ืื–ื•ื™ ืขืก ืืจื‘ืขื˜? PostgreSQL ืื™ื– ื’ืขื ื™ืฆื˜ ื•ื•ื™ ืึท "ื•ื•ื™ืจื˜ื•ืึทืœ ืžืึทืฉื™ืŸ". ืขืก ืื™ื– ืึท ืงืึธืžืคึผืœืขืงืก ืึทืœื’ืขืจื™ื“ืึทื ื™ืŸ ื•ื•ืึธืก ื‘ื•ื™ืขืŸ ืงื•ื•ื™ืจื™ื–. ื“ืึธ ืžืงื•ืจ. ืื•ืŸ ืขืก ืื™ื– ื ื™ื˜ ื ืึธืจ ืึท ื’ืจื•ื™ืก ื’ืึทื ื’ ืคื•ืŸ ื›ื™ื•ืจื™ืกื˜ื™ืงืก ืžื™ื˜ ืึท ื‘ื™ื ื˜ืœ ืคื•ืŸ ืื•ื™ื‘. ืึทื–ื•ื™, ืื•ื™ื‘ ืื™ืจ ื”ืึธื‘ืŸ ืึท ืคึผืึธืจ ืคื•ืŸ ื—ื“ืฉื™ื ืฆื• ืœืขืจื ืขืŸ, ืื™ืจ ืงืขื ืขืŸ ืคึผืจื•ื‘ื™ืจืŸ ืฆื• ืคึฟืึทืจืฉื˜ื™ื™ืŸ ืึทืจืงืึทื˜ืขืงื˜ืฉืขืจ.

ื˜ื•ื˜ ืขืก ืึทืจื‘ืขื˜ ื™ืคืขืงื˜ื™ื•ื•ืœื™? ื’ืึทื ืฅ ืขืคืขืงื˜ื™ื•ื•. ืฆื•ื ื‘ืึทื“ื•ื™ืขืจืŸ, ื“ืึธืก ืื™ื– ืฉื•ื•ืขืจ ืฆื• ื‘ืึทื•ื•ื™ื™ึทื–ืŸ. ืื™ืš ืงืขืŸ ื ืึธืจ ื–ืึธื’ืŸ ืึทื– ืื•ื™ื‘ ืื™ืจ ื‘ืึทื˜ืจืึทื›ื˜ืŸ ื“ื™ ื˜ื•ื™ื–ื ื˜ืขืจ ืคื•ืŸ ืคึฟืจืื’ืŸ ื•ื•ืึธืก ืขืงืกื™ืกื˜ื™ืจืŸ ืื™ืŸ ื’ืจื•ื™ืก ืึทืคึผืœืึทืงื™ื™ืฉืึทื ื–, ื–ื™ื™ ื–ืขื ืขืŸ ืื™ืŸ ื“ื•ืจื›ืฉื ื™ื˜ืœืขืš ืžืขืจ ืขืคืขืงื˜ื™ื•ื• ื•ื•ื™ ื“ื™ ืคื•ืŸ ืึท ื’ื•ื˜ ื“ืขื•ื•ืขืœืึธืคึผืขืจ. ืึท ื•ื™ืกื’ืขืฆื™ื™ื›ื ื˜ SQL ืคึผืจืึธื’ืจืึทืžื™ืกื˜ ืงืขื ืขืŸ ืฉืจื™ื™ึทื‘ืŸ ืงื™ื™ืŸ ืึธื ืคึฟืจืขื’ ืžืขืจ ื™ืคื™ืฉืึทื ื˜ืœื™, ืึธื‘ืขืจ ืžื™ื˜ ืึท ื˜ื•ื™ื–ื ื˜ ืงื•ื•ื™ืจื™ื– ืขืจ ืคืฉื•ื˜ ื•ื•ืขื˜ ื ื™ืฉื˜ ื”ืึธื‘ืŸ ื“ื™ ืžืึธื•ื˜ืึทื•ื•ื™ื™ืฉืึทืŸ ืึธื“ืขืจ ืฆื™ื™ื˜ ืฆื• ื˜ืึธืŸ ื“ืึธืก. ื“ืขืจ ื‘ืœื•ื™ื– ื–ืึทืš ืื™ืš ืงืขื ืขืŸ ืื™ืฆื˜ ืฆื™ื˜ื™ืจืŸ ื•ื•ื™ ื“ืขืจื•ื•ื™ื™ึทื– ืคื•ืŸ ื™ืคืขืงื˜ื™ื•ื•ื ืึทืก ืื™ื– ืึทื– ืขื˜ืœืขื›ืข ืคึผืจืึทื“ื–ืฉืขืงืก ื–ืขื ืขืŸ ืืจื‘ืขื˜ืŸ ืื•ื™ืฃ ื“ื™ ืคึผืœืึทื˜ืคืึธืจืžืข ื’ืขื‘ื•ื™ื˜ ืื•ื™ืฃ ื“ืขื DBMS ืขืจืคึผ ืกื™ืกื˜ืขืžืขืŸ, ื•ื•ืึธืก ื”ืึธื‘ืŸ ื˜ื•ื™ื–ื ื˜ืขืจ ืคื•ืŸ ืคืึทืจืฉื™ื“ืขื ืข ืžืึทื˜ืขืจื™ืึทืœื™ื–ืขื“ ืคืึทื ื’ืงืฉืึทื ื–, ืžื™ื˜ ื˜ื•ื™ื–ื ื˜ืขืจ ืคื•ืŸ ื ื™ืฆืขืจืก ืื•ืŸ ื˜ืขืจืึทื‘ื™ื˜ืข ื“ืึทื˜ืึทื‘ื™ื™ืกื™ื– ืžื™ื˜ ื”ื•ื ื“ืขืจื˜ืขืจ ืคื•ืŸ ืžื™ืœื™ืึทื ื– ืคื•ืŸ ืจืขืงืึธืจื“ืก ืคืœื™ืกื ื“ื™ืง ืื•ื™ืฃ ืึท ืจืขื’ื•ืœืขืจ ืฆื•ื•ื™ื™-ืคึผืจืึทืกืขืกืขืจ ืกืขืจื•ื•ืขืจ. ืึธื‘ืขืจ, ื•ื•ืขืจ ืขืก ื™ื– ืงืขื ืขืŸ ืงืึธื ื˜ืจืึธืœื™ืจืŸ / ืจื™ืคื™ื•ื˜ ื“ื™ ื™ืคืขืงื˜ื™ื•ื•ื ืึทืก ื“ื•ืจืš ื“ืึทื•ื ืœืึธื•ื“ื™ื ื’ ืคึผืœืึทื˜ืคืึธืจืžืข ืื•ืŸ PostgreSQL, ืื•ื™ืกื’ืขื“ืจื™ื™ื˜ ืื•ื™ืฃ ืœืึธื’ื™ื ื’ ืกืงืœ ืงื•ื•ื™ืจื™ื– ืื•ืŸ ื˜ืจื™ื™ื ื’ ืฆื• ื˜ื•ื™ืฉืŸ ื“ื™ ืœืึธื’ื™ืง ืื•ืŸ ื“ืึทื˜ืŸ ื“ืึธืจื˜.

ืื™ืŸ ื“ื™ ืคืืœื’ืขื ื“ืข ืึทืจื˜ื™ืงืœืขืŸ, ืื™ืš ื•ื•ืขืœ ืื•ื™ืš ืจืขื“ืŸ ื•ื•ืขื’ืŸ ื•ื•ื™ ืื™ืจ ืงืขื ืขืŸ ืฉื˜ืขืœืŸ ืจื™ืกื˜ืจื™ืงืฉืึทื ื– ืื•ื™ืฃ ืคืึทื ื’ืงืฉืึทื ื–, ืึทืจื‘ืขื˜ ืžื™ื˜ ื˜ื•ื™ืฉืŸ ืกืขืฉืึทื ื–, ืื•ืŸ ืคื™ืœ ืžืขืจ.

ืžืงื•ืจ: www.habr.com

ืœื™ื™ื’ืŸ ืึท ื‘ืึทืžืขืจืงื•ื ื’