啥意思?怎么连接的,left jion / right jion / inner jion......?还是你在select ..........里只指定了A.*
怎么个连接法? LEFT JOIN , INNER JION , FULL JOIN?
SELECT e.name,e.sex,e.id,e.salary,e.dno FROM Employee e,Department d WHERE e.dno = d.dnumber输出结果和SELECT e.name,e.sex,e.id,e.salary,e.dno FROM Employee e一样不懂!
SELECT e.name,e.sex,e.id,e.salary,e.dno FROM Employee e,Department d WHERE e.dno = d.dnumber输出结果和SELECT e.name,e.sex,e.id,e.salary,e.dno FROM Employee e一样不懂!
啥意思?怎么连接的,left jion / right jion / inner jion......?还是你在select ..........里只指定了A.*
LEFT JOIN , INNER JION , FULL JOIN?
FROM Employee e,Department d
WHERE e.dno = d.dnumber输出结果和SELECT e.name,e.sex,e.id,e.salary,e.dno
FROM Employee e一样不懂!
SELECT e.name,e.sex,e.id,e.salary,e.dno
FROM Employee e,Department d
WHERE e.dno = d.dnumber输出结果和SELECT e.name,e.sex,e.id,e.salary,e.dno
FROM Employee e一样不懂!
你查询的全部是一个表里面的内容啊 有可能的情况是Employee表的dno 全部包含在Department 的Dnumber字段中