9 SQLååãããã³å¯ååã ãã®ç« ã§ã¯ãSQLååãããã³å¯ååãã«ã¤ãã¦èª¬æãã¾ãã ãã®ç« ã§ã¯ã次ã®å 容ã説æãã¾ãã ååãããã³å¯ååã åç´ãªååãã®ä½æ é層ååã UNION [ALL]ãINTERSECTããã³MINUSæ¼ç®å ååãçµæã®ã½ã¼ã çµå å¯ååãã®ä½¿ç¨æ¹æ³ ãã¹ããããå¯ååãã®ãã¹ãè§£é¤ DUAL表ããã®é¸æ åæ£ååã ååãããã³å¯ååã ååãã¨ã¯ã1ã¤ä»¥ä¸ã®è¡¨ã¾ãã¯ãã¥ã¼ãããã¼ã¿ãæ¤ç´¢ããæä½ã®ãã¨ã§ãããã®ããã¥ã¢ã«ã§ã¯ããããã¬ãã«ã®SELECTæãååãã¨ãããä»ã®SQLæã®ä¸ã§ãã¹ããããååããå¯ååãã¨ããã¾ãã ãã®é ã§ã¯ãååãããã³å¯ååãã®ç¨®é¡ããã³ãã®ä½¿ç¨æ¹æ³ã«ã¤ãã¦èª¬æãã¾ãããã®ç« ã§ã¯ããããã¬ãã«ã®æ§æã«ã¤ãã¦èª¬æãã¾ãããã¹ã¦ã®å¥ã®ãã¹ã¦ã®æ§æããã³ãã®æã®ã»ãã³ãã£ã¯ã¹ã«ã¤ãã¦ã¯ããSELECTããåç §ãã¦ãã
{{#tags}}- {{label}}
{{/tags}}