MAXã?¯è¡Œã?®é›†å?ˆã?‹ã‚‰æœ€å¤§ã?®å€¤ã‚’求ã‚?る集約関数ã?§ã?™ã€‚(集約 (集å?ˆé–¢æ•°)ã‚’å?‚ç…§ã?—ã?¦ã??ã? ã?•ã?„。) MAXã?¯çµ„ã?¿è¾¼ã?¾ã‚Œã?Ÿãƒ‡ãƒ¼ã‚¿åž‹ã?®å¼?ã?«å¯¾ã?—ã?¦ã?®ã?¿é?©ç”¨ã?™ã‚‹ã?“ã?¨ã?Œã?§ã??ã?¾ã?™ã€‚ (CHARã€?VARCHARã€?DATEã€?TIMEã€?CHAR FOR BIT DATAç‰ã‚’å?«ã?¿ã?¾ã?™ã€‚)
MAX ( [ DISTINCT | ALL ] å¼? )
SELECT COUNT (DISTINCT flying_time), MAX (DISTINCT miles) FROM Flights
å¼?ã?¯è¤‡æ•°ã?®åˆ—ã?¸ã?®å?‚ç…§ã‚„å¼?ã‚’å?«ã‚€ã?“ã?¨ã?Œã?§ã??ã?¾ã?™ã?Œã€?ä»–ã?®é›†ç´„や副å•?å?ˆã?›ã‚’å?«ã‚€ã?“ã?¨ã?¯ã?§ã??ã?¾ã?›ã‚“。 ã?¾ã?Ÿçµ„è¾¼ã?¿ã?®ãƒ‡ãƒ¼ã‚¿åž‹ã?«è©•価ã?•れã?ªã?‘れã?°ã?ªã‚Šã?¾ã?›ã‚“。 従ã?£ã?¦çµ„è¾¼ã?¿ã?®ãƒ‡ãƒ¼ã‚¿åž‹ã?¨è©•価ã?•れるメソッドを呼ã?¶ã?“ã?¨ã?Œã?§ã??ã?¾ã?™ã€‚ (例ã?ˆã?°java.lang.Integerã‚„intã‚’è¿”ã?™ãƒ¡ã‚½ãƒƒãƒ‰ã?¯INTEGERã?¨è©•価ã?•れã?¾ã?™ã€‚) ã‚‚ã?—å¼?ã?ŒNULLã?¨è©•価ã?•れã?Ÿå ´å?ˆã€?集約ã?«ã?Šã?„ã?¦ã??ã?®å€¤ã?¯ç„¡è¦–ã?•れã?¾ã?™ã€‚
CHARã€?VARCHARã?«ã?¤ã?„ã?¦ã?¯ã€?値ã?®æœ«å°¾ã?«ã?‚る空白文å—列ã?¯ã€?MAXã?®æŒ¯ã‚‹èˆžã?„ã?«å½±éŸ¿ã?Œã?‚りã?¾ã?™ã€‚ ã?Ÿã?¨ã?ˆã?°ã€?'z'ã?¨'z 'ã?®ä¸¡æ–¹ã?Œåˆ—ã?«æ ¼ç´?ã?•れã?¦ã?„ã?Ÿå ´å?ˆã€?空白ã?¯æ¯”較ã?«ã?¦ç„¡è¦–ã?•れるã?®ã?§çµ?æžœã?¯ä¸?定ã?§ã?™ã?Œã€?何れã?‹ç‰‡æ–¹ã?®å€¤ã?Œè¿”ã?•れã?¾ã?™ã€‚
çµ?æžœã?®ãƒ‡ãƒ¼ã‚¿åž‹ã?¯MAXã?Œå‹•作ã?™ã‚‹å¼?ã?¨å?Œã?˜ã‚‚ã?®ã?¨ã?ªã‚Šã?¾ã?™ã€‚(オーãƒ?ーフãƒãƒ¼ã?™ã‚‹ã?“ã?¨ã?¯ã?‚りã?¾ã?›ã‚“。)
-- FlightAvailabilityã?¨ã?„ã?†è¡¨ã?‹ã‚‰æœ€è¿‘ã?®æ—¥ä»˜ã‚’探ã?™ã€‚ SELECT MAX (flight_date) FROM FlightAvailability -- ã??れã?žã‚Œã?®ç©ºæ¸¯ã‚’出発ã?™ã‚‹æœ€ã‚‚é•·è·?離ã?®ä¾¿ã‚’探ã?™ã€‚ -- ã?ªã?Š10時間以上ã?®ä¾¿ã?®ã?¿ã?¨ã?™ã‚‹ã€‚ SELECT MAX(flying_time), orig_airport FROM Flights GROUP BY orig_airport HAVING MAX(flying_time) > 10