COUNTæ¯ç»è®¡æ»¡è¶³æ¡ä»¶çæ°éï¼ä¾å¦ä¸é¢çè¯å¥æ¥è¯¢æ»çè®°å½æ°ï¼
SELECT COUNT(*) FROM tab;
ä¾å¦ä¸é¢çè¯å¥æ¾ç¤ºç·æ§çè®°å½æ°ï¼
SELECT COUNT(*) FROM tab WHERE sex='ç·';
åå¦ä¸é¢çè¯å¥åæ¶æ¾ç¤ºç·æ§å女æ§çè®°å½æ°ï¼
SELECT sex,COUNT(*) FROM tab GROUP BY sex;
温馨提示:答案为网友推荐,仅供参考