2007/8/2521:27 ãSQLãDISTINCTå¥ã®è¨è¿°ä½ç½®ã«ããå®è¡çµæã®éãã«ã¤ã㦠DISTINCTã®ä½¿ãæ¹ã«ã¯ã以ä¸ã®2種é¡ãããã 1.åå¾ããé¸æãªã¹ãï¼é ç®ãªã¹ãï¼ã®åã«DISTINCTãè¨è¿°ãã ä¾ï¼SELECT DISTINCT COUNT(Column_Name) ... 2.éè¨é¢æ°å ã«DISTINCTãè¨è¿°ãã ä¾ï¼SELECT COUNT(DISTINCT Column_Name) ... ä¸è¨ã®å®è¡çµæã§ã¯ãéè¤ãæé¤ãã対象ã«å·®ç°ãçºçããã ãã®å·®ç°ã¯ã以ä¸ã®éãã§ããã 1.DISTINCT COUNT(Column_Name)ã®å ´åãé¸æé ç®ã®çµã¿åãããéè¤ããªãã¬ã³ã¼ã件æ°ã表示ããã 2.COUNT(DISTINCT Column_Name)ã®å ´åãåä½ã®é ç®ï¼Column_Nameï¼ã®éè¤ãã¦ããªã件æ°ï¼ç¨®é¡æ°ï¼ãåå¾ããã 以ä¸ãå®è¡çµ
{{#tags}}- {{label}}
{{/tags}}