SUM ã?¯è¡Œã?®é›†å?ˆã?«æ¸¡ã?£ã?¦å?ˆè¨ˆå€¤ã‚’計算ã?™ã‚‹é›†ç´„関数ã?§ã?™ã€‚(集約 (集å?ˆé–¢æ•°)ã‚’å?‚ç…§ã?—ã?¦ã??ã? ã?•ã?„。) SUMã?¯æ•°å€¤åž‹ã?®å¼?ã?«å¯¾ã?—ã?¦ã?®ã?¿ã€?é?©ç”¨ã?™ã‚‹ã?“ã?¨ã?Œã?§ã??ã?¾ã?™ã€‚
SUM ( [ DISTINCT | ALL ] å¼? )
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SELECT AVG (DISTINCT flying_time), SUM (DISTINCT miles) FROM Flights
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関数ã?®çµ?æžœã?®åž‹ã?¯ã€?関数ã?Œä½œç”¨ã?—ã?¦ã?„ã‚‹å¼?ã?®åž‹ã?¨å?Œã?˜ã?§ã?™ã€‚(オーãƒ?ーフãƒãƒ¼ã?™ã‚‹å?¯èƒ½æ€§ã‚‚ã?‚りã?¾ã?™ã€‚)
-- 全��エコノミーシートを数���。 SELECT SUM (economy_seats) FROM Airlines; -- SUMを複数�列���照�使���。 -- (購入�れ����計を計算���。) SELECT SUM (economy_seats_taken + business_seats_taken + firstclass_seats_taken) as seats_taken FROM FLIGHTAVAILABILITY;