从表中选取

如需从 MySQL 中的表中进行选择，请使用 "SELECT" 语句：

示例代码：

从表 "customers" 中选取所有记录，并显示结果：

import mysql.connector
mydb = mysql.connector.connect(
  host="localhost",
  user="yourusername",
  passwd="yourpassword",
  database="mydatabase"
)
mycursor = mydb.cursor()
mycursor.execute("SELECT * FROM customers")
myresult = mycursor.fetchall()
for x in myresult:
  print(x)

完整实例：

import mysql.connector
mydb = mysql.connector.connect(
  host="localhost",
  user="myusername",
  passwd="mypassword",
  database="mydatabase"
)
mycursor = mydb.cursor()
mycursor.execute("SELECT * FROM customers")
myresult = mycursor.fetchall()
for x in myresult:
  print(x)

注释：我们用了 fetchall() 方法，该方法从最后执行的语句中获取所有行。

选取列

如需只选择表中的某些列，请使用 "SELECT" 语句，后跟列名：

示例代码：

仅选择名称和地址列：

import mysql.connector
mydb = mysql.connector.connect(
  host="localhost",
  user="yourusername",
  passwd="yourpassword",
  database="mydatabase"
)
mycursor = mydb.cursor()
mycursor.execute("SELECT name, address FROM customers")
myresult = mycursor.fetchall()
for x in myresult:
  print(x)

完整实例：

import mysql.connector
mydb = mysql.connector.connect(
  host="localhost",
  user="myusername",
  passwd="mypassword",
  database="mydatabase"
)
mycursor = mydb.cursor()
mycursor.execute("SELECT name, address FROM customers")
myresult = mycursor.fetchall()
for x in myresult:
  print(x)

使用 fetchone() 方法

如果您只对一行感兴趣，可以使用 fetchone() 方法。

fetchone() 方法将返回结果的第一行：

示例代码：

仅获取一行：

import mysql.connector
mydb = mysql.connector.connect(
  host="localhost",
  user="yourusername",
  passwd="yourpassword",
  database="mydatabase"
)
mycursor = mydb.cursor()
mycursor.execute("SELECT * FROM customers")
myresult = mycursor.fetchone()
print(myresult)

完整实例：

import mysql.connector
mydb = mysql.connector.connect(
  host="localhost",
  user="myusername",
  passwd="mypassword",
  database="mydatabase"
)
mycursor = mydb.cursor()
mycursor.execute("SELECT * FROM customers")
myresult = mycursor.fetchone()
print(myresult)