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GROUP BY 列å?? [ , 列å?? ] *
列å?? ã?¯å•?ã?„å?ˆã‚?ã?›ã?«ã?¦å?¯è¦–ã?§ã?ªã?‘れã?°ã?ªã‚Šã?¾ã?›ã‚“。å•?ã?„å?ˆã‚?ã?›ã?«ã?¦ä¸?å?¯è¦–ã?ªåˆ—ã?§ã?‚ã?£ã?¦ã?¯ã?ªã‚Šã?¾ã?›ã‚“。 例ã?ˆã?°ã€?GROUP BY節ã?Œå‰¯å•?ã?„å?ˆã‚?ã?›ã?«ã?‚ã?£ã?Ÿå ´å?ˆã€?ã??ã?®ç¯€ã?¯å‰¯å•?ã?„å?ˆã‚?ã?›ã?®å¤–ã?«ã?‚ã‚‹å•?ã?„å?ˆã‚?ã?›ã?®åˆ—ã‚’å?‚ç…§ã?—ã?¦ã?¯ã?ªã‚Šã?¾ã?›ã‚“。
GROUP BY節をæŒ?ã?¤é?¸æŠžå¼?ã?«ã?‚ã‚‹é?¸æŠžé …ç›®ã?¯é›†ç´„ã?‹åˆ†é¡žåˆ—ã?§ã?ªã?‘れã?°ã?ªã‚Šã?¾ã?›ã‚“。
-- airportã?§åˆ†é¡žã?•れã?Ÿflightsã?®ã€? -- flying_timesã?®å¹³å?‡ã‚’探ã?™ã€‚ SELECT AVG (flying_time), orig_airport FROM Flights GROUP BY orig_airport SELECT MAX(city_name), region FROM Cities, Countries WHERE Cities.country_ISO_code = Countries.country_ISO_code GROUP BY region -- smallintã?«ã‚ˆã‚‹åˆ†é¡ž SELECT ID, AVG(SALARY) FROM SAMP.STAFF GROUP BY ID -- AVGSALARYã€?EMPCOUNT列ã?¨ã€?DEPTNO列をAS節ã?«ã‚ˆã‚Šå?–å¾—ã?™ã‚‹ã€‚ -- ã?•らã?«OTHERSã?¨ã?„ã?†ç›¸é–¢å??ã?§ã€?WORKDEPT列ã?«ã‚ˆã‚‹åˆ†é¡žã‚’行ã?†ã€‚ SELECT OTHERS.WORKDEPT AS DEPTNO, AVG(OTHERS.SALARY) AS AVGSALARY, COUNT(*) AS EMPCOUNT FROM SAMP.EMPLOYEE OTHERS GROUP BY OTHERS.WORKDEPT