为此,请使用联接概念。让我们首先创建一个-
create table DemoTable1389 -> ( -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> StudentMarks int -> );
使用insert命令在表中插入一些记录。在这里,我们还插入了重复值-
insert into DemoTable1389(StudentMarks) values(40); insert into DemoTable1389(StudentMarks) values(40); insert into DemoTable1389(StudentMarks) values(68); insert into DemoTable1389(StudentMarks) values(78); insert into DemoTable1389(StudentMarks) values(97); insert into DemoTable1389(StudentMarks) values(97); insert into DemoTable1389(StudentMarks) values(97);
使用select语句显示表中的所有记录-
select * from DemoTable1389;
这将产生以下输出-
+-----------+--------------+ | StudentId | StudentMarks | +-----------+--------------+ | 1 | 40 | | 2 | 40 | | 3 | 68 | | 4 | 78 | | 5 | 97 | | 6 | 97 | | 7 | 97 | +-----------+--------------+ 7 rows in set (0.00 sec)
以下是选择多个最大值的查询-
select tbl.StudentId,tbl.StudentMarks from DemoTable1389 tbl -> join ( select max(StudentMarks) as MaxMarks from DemoTable1389) tbl1 -> on tbl1.MaxMarks=tbl.StudentMarks;
这将产生以下显示最大值的输出,以及重复项-
+-----------+--------------+ | StudentId | StudentMarks | +-----------+--------------+ | 5 | 97 | | 6 | 97 | | 7 | 97 | +-----------+--------------+ 3 rows in set (0.00 sec)