用于对行值求和并对结果进行排序的 MySQL 查询是什么?


为此,可将 GROUP BY 与 ORDER BY 子句一起使用。我们先创建一个表 -

mysql> create table DemoTable1499
   -> (
   -> StudentName varchar(20),
   -> StudentMarks int
   -> );
Query OK, 0 rows affected (0.46 sec)

使用 insert 命令在表中插入一些记录 -

mysql> insert into DemoTable1499 values('Chris',56);
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable1499 values('David',78);
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable1499 values('Bob',98);
Query OK, 1 row affected (0.18 sec)
mysql> insert into DemoTable1499 values('Chris',45);
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable1499 values('David',98);
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable1499 values('Bob',58);
Query OK, 1 row affected (0.11 sec)

使用 select 语句显示表中的所有记录 -

Mysql> select * from DemoTable1499;

这将生成以下输出 -

+-------------+--------------+
| StudentName | StudentMarks |
+-------------+--------------+
| Chris       |           56 |
| David       |           78 |
| Bob         |           98 |
| Chris       |           45 |
| David       |           98 |
| Bob         |           58 |
+-------------+--------------+
6 rows in set (0.00 sec)

以下是用于对行值求和并对结果排序的查询 -

mysql> select StudentName,sum(StudentMarks) as TotalSum from DemoTable1499
   -> group by StudentName
   -> order by TotalSum desc;

这将生成以下输出 -

+-------------+----------+
| StudentName | TotalSum |
+-------------+----------+
| David       |      176 |
| Bob         |      156 |
| Chris       |      101 |
+-------------+----------+
3 rows in set (0.00 sec)

更新于:2019-12-11

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