Python3 notes

排序

查询结果排序可以使用 ORDER BY 语句，默认的排序方式为升序，关键字为 ASC，如果要设置降序排序，可以设置关键字 DESC。

demo_mysql_test.py

按 name 字段字母的升序排序：

importmysql.connectormydb = mysql.connector.connect(  host="localhost",   user="root",   passwd="123456",   database="runoob_db")mycursor = mydb.cursor()sql = "SELECT * FROM sites ORDER BY name"mycursor.execute(sql)myresult = mycursor.fetchall()forxinmyresult:   print(x)

执行代码，输出结果为：

(3,'Github','https://www.github.com')

(2,'Google','https://www.google.com')

(1,'RUNOOB','https://www.runoob.com')

(5,'stackoverflow','https://www.stackoverflow.com/')

(4,'Taobao','https://www.taobao.com')

(6,'Zhihu','https://www.zhihu.com')

降序排序实例：

demo_mysql_test.py

按 name 字段字母的降序排序：

importmysql.connectormydb = mysql.connector.connect(  host="localhost",   user="root",   passwd="123456",   database="runoob_db")mycursor = mydb.cursor()sql = "SELECT * FROM sites ORDER BY name DESC"mycursor.execute(sql)myresult = mycursor.fetchall()forxinmyresult:   print(x)

执行代码，输出结果为：

(6,'Zhihu','https://www.zhihu.com')

(4,'Taobao','https://www.taobao.com')

(5,'stackoverflow','https://www.stackoverflow.com/')

(1,'RUNOOB','https://www.runoob.com')

(2,'Google','https://www.google.com')

(3,'Github','https://www.github.com')