sql (8) AVG

SQL avg syntax
SELECT AVG(column_name) FROM table_name
New table:
StudentS

S_id Grade Name phone
1 98 Xiao Ming 123456
2 97 Xiao Huang 232456
3 95 Xiao Li 987654
4 93 Xiao Xiao 654321
5 90 Wei Wei 321065

查询：
SELECT AVG(Grade) AS GradeAverage FROM StudentS

Result:
GradeAverage
94

We want to find the names of students whose Grade values ​​are higher than the average Grade.

查询：
SELECT Name FROM StudentS
WHERE Grade>(
SELECT AVG(Grade) FROM StudentS

Effect:

Name
1 Xiaoming2
Xiaohuang3
Xiaoli

 

2018-04-27   14:37:59