HAVING 節

HAVING節ã?«ã‚ˆã‚Šé?¸æŠžå¼?ã?®GROUP BYã?®çµ?æžœã?Œçµžã‚Šè¾¼ã?¾ã‚Œã?¾ã?™ã€‚WHERE節ã?Œé?¸æŠžåˆ—一覧ã?«ä½œç”¨ã?™ã‚‹ã?®ã?¨ã?¯ç•°ã?ªã‚Šã€?HAVING節ã?¯è¡¨ã?‹ã‚‰åˆ†é¡žã?•れã?Ÿéƒ¨åˆ†é›†å?ˆã?«å¯¾ã?—ã?¦ä½œç”¨ã?—ã?¾ã?™ã€‚ã‚‚ã?—GROUP BY節ã?Œã?ªã?‘れã?°ã€?HAVING節ã?¯çµ?果をå?˜ç‹¬ã?®åˆ†é¡žã?¨è¦‹ã?ªã?—ã?¦ä½œç”¨ã?—ã?¾ã?™ã€‚ SELECT節ã?«ã?¦GROUP BYå?¥ã?®ã?ªã?„列を直接å?‚ç…§ã?™ã‚‹ã?“ã?¨ã?¯ã?§ã??ã?¾ã?›ã‚“。ã?—ã?‹ã?—定数や集約ã€?特殊変数をå?‚ç…§ã?™ã‚‹ã?“ã?¨ã?¯ã?§ã??ã?¾ã?™ã€‚

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HAVING 検索�件
検索æ?¡ä»¶ã?¯ç‰¹æ®Šã?ªçœŸå?½å¼?ã?§ã€?分類列(GROUP BY 節をå?‚ç…§ã?—ã?¦ã??ã? ã?•ã?„。)ã?‹ã€?集約å¼?ã?®ä¸€éƒ¨ã?§ã?‚る列ã?®ã?¿å?«ã‚?る事ã?Œã?§ã??ã?¾ã?™ã€‚ 例ã?ˆã?°ä»¥ä¸‹ã?®ä¾‹ã?§ã?¯ã€?SALARYã?¨ã?„ã?†åˆ—ã?¯åˆ†é¡žã?®åˆ—や集約ã€?副å•?ã?„å?ˆã‚?ã?›ã?«ã?‚る列ã?§ã?¯ã?ªã?„ã?®ã?§ã€?ã?“ã?®æ–‡ã?¯ä¸?æ­£ã?§ã?™ã€‚
-- SELECT COUNT(*)
-- FROM SAMP.STAFF
-- GROUP BY ID
-- HAVING SALARY > 15000

HAVING節ã?®é›†ç´„ã?¯SELECTã?®ä¸€è¦§ã?«ã?ªã??ã?¦ã‚‚ã?‹ã?¾ã?„ã?¾ã?›ã‚“。 ã‚‚ã?—HAVING節ã?Œå‰¯å•?ã?„å?ˆã‚?ã?›ã‚’å?«ã‚€ã?ªã‚‰ã?°ã€?ã??ã?®å‰¯å•?ã?„å?ˆã‚?ã?›ã?¯åˆ†é¡žã?®åˆ—ã?«ã?¤ã?„ã?¦ã?®ã?¿ã€?外ã?®å•?ã?„å?ˆã‚?ã?›ã‚’å?‚ç…§ã?™ã‚‹ã?“ã?¨ã?Œã?§ã??ã?¾ã?™ã€‚

-- 2席以上�航路����エコノミー席��計を調�る。
SELECT SUM(ECONOMY_SEATS_TAKEN), AIRLINE_FULL
FROM FLIGHTAVAILABILITY, AIRLINES
WHERE SUBSTR(FLIGHTAVAILABILITY.FLIGHT_ID, 1, 2) = AIRLINE
GROUP BY AIRLINE_FULL
HAVING COUNT(*) > 1