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AVG ( [ DISTINCT | ALL ] å¼? )
DISTICTを指定ã?™ã‚‹ã?¨ã€?é‡?複ã?Œå?–り除ã?‹ã‚Œã?¾ã?™ã€‚ ALLを指定ã?™ã‚‹ã?¨ã€?é‡?複を残ã?—ã?¾ã?™ã€‚ALLã‚‚DISTINCTも指定ã?•れã?ªã?„å ´å?ˆã?®æ—¢å®šã?¯ALLã?§ã?™ã€‚ 例ã?ˆã?°ã€?列ã?®å€¤ã?Œ1.0ã€?1.0ã€?1.0ã€?1.0ã€?2.0ã? ã?£ã?Ÿã?¨ã?—ã?¾ã?™ã€‚ã?“ã?®å ´å?ˆã€?AVG(col)ã?¯AVG(DISTINCT col)よりå°?ã?•ã?ªå€¤ã‚’è¿”ã?—ã?¾ã?™ã€‚
SELECT AVG (DISTINCT flying_time), SUM (DISTINCT miles) FROM Flights
å¼?ã?«ã?¯è¤‡æ•°åˆ—ã?¸ã?®å?‚ç…§ã‚„å¼?ã?Œã?‚ã?£ã?¦ã?‹ã?¾ã?„ã?¾ã?›ã‚“ã?Œã€?ä»–ã?®é›†ç´„や副å•?å?ˆã?›ã?Œã?‚ã?£ã?¦ã?¯ã?ªã‚Šã?¾ã?›ã‚“。 ã?¾ã?Ÿè©•価çµ?æžœã?¯SQL-92ã?®æ•°å€¤åž‹ã?§ã?ªã?‘れã?°ã?ªã‚Šã?¾ã?›ã‚“。ã?—ã?Ÿã?Œã?£ã?¦SQL-92ã?®åž‹ã?«è©•価ã?•れる関数ã?ªã‚‰å‘¼ã?¶ã?“ã?¨ã?Œã?§ã??ã?¾ã?™ã€‚ã‚‚ã?—評価çµ?æžœã?ŒNULLã?§ã?‚ã?£ã?Ÿå ´å?ˆã€?集約ã?«ã?¦ã??ã?®å€¤ã?¯çœ?ã?‹ã‚Œã?¾ã?™ã€‚
SELECT AVG(c1) FROM (VALUES (1), (1), (1), (1), (2)) AS myTable (c1)
SELECT AVG(CAST (c1 AS DOUBLE PRECISION)) FROM (VALUES (1), (1), (1), (1), (2)) AS myTable (c1)