MySQL-获得注册人数最多的年份
我在MySQL中有一个表(名为EMP):MySQL-获得注册人数最多的年份,mysql,select,numbers,max,Mysql,Select,Numbers,Max,我在MySQL中有一个表(名为EMP): EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO ----- ----- ------- ---- -------- -------- ------- ------ 7369 SMITH CLERK 7902 13-JUN-83 800.00 20 7499 ALLEN SALESMAN 7698 15-AUG-83 1,60
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
----- ----- ------- ---- -------- -------- ------- ------
7369 SMITH CLERK 7902 13-JUN-83 800.00 20
7499 ALLEN SALESMAN 7698 15-AUG-83 1,600.00 300.00 30
7521 WARD SALESMAN 7698 26-MAR-84 1,250.00 500.00 30
7566 JONES MANAGER 7839 31-OCT-83 2,975.00 20
7654 MARTIN SALESMAN 7698 05-DEC-83 1,250.00 1,400.00 30
7698 BLAKE MANAGER 7839 11-JUL-84 2,850.00 30
7782 CLARK MANAGER 7839 14-MAY-84 2,450.00 10
7788 SCOTT ANALYST 7566 05-MAR-84 3,000.00 20
7839 KING PRESIDENT 09-JUL-84 5,000.00 10
7844 TURNER SALESMAN 7698 04-JUN-84 1,500.00 .00 30
7876 ADAMS CLERK 7788 04-JUN-84 1,100.00 20
7900 JAMES CLERK 7698 23-JUL-84 950.00 30
7902 FORD ANALYST 7566 05-DEC-83 3,000.00 20
7934 MILLER CLERK 7782 21-NOV-83 1,300.00 10
如何编写Select查询,返回注册员工(行)最多的年份(HIREDATE列)?关于:
SELECT COUNT(1), YEAR(HIREDATE) FROM EMP GROUP BY YEAR(HIREDATE);
那么:
SELECT COUNT(1), YEAR(HIREDATE) FROM EMP GROUP BY YEAR(HIREDATE);
试试这个:
select year(hiredate), count(*) from emp
group by year(hiredate) order by 2 desc limit 1
试试这个:
select year(hiredate), count(*) from emp
group by year(hiredate) order by 2 desc limit 1
试一试
试一试
那怎么办
SELECT YEAR(hiredate) FROM emp
GROUP BY YEAR(hiredate)
ORDER BY COUNT(*) DESC
LIMIT 1
?怎么样
SELECT YEAR(hiredate) FROM emp
GROUP BY YEAR(hiredate)
ORDER BY COUNT(*) DESC
LIMIT 1
这真的是MySQL吗?如果是的话,这是一个真正的日期列类型还是一个包含dd-MON-yy字符串的CHAR列?在我看来,它像是Oracle日期输出格式。。。MySQL使用YYYY-MM-DD。这真的是MySQL吗?如果是的话,这是一个真正的日期列类型还是一个包含dd-MON-yy字符串的CHAR列?在我看来,它像是Oracle日期输出格式。。。MySQL使用YYYY-MM-DD。他想用max countThank返回年份值,但没有注意到这一点。他应该添加order by,就像Wisset的回答一样。他想用max CountThank返回年份值,但没有注意到这一点。他应该增加秩序,就像智慧的回答一样。