Python MySQL查询限制方式详解

SELECT column_name(s)
FROM table_name
LIMIT number;

SELECT *
FROM students
LIMIT 5;

SELECT column_name(s)
FROM table_name
LIMIT number OFFSET offset;

SELECT *
FROM students
LIMIT 5 OFFSET 5;

SELECT column_name(s)
FROM table_name
LIMIT number OFFSET offset;

SELECT *
FROM students
LIMIT 5 OFFSET 5;

import mysql.connector
mydb = mysql.connector.connect(
  host="localhost",
  user="您的用户名",
  password="您的密码",
  database="我的数据库"
)
mycursor = mydb.cursor()
mycursor.execute("SELECT * FROM customers LIMIT 5")
myresult = mycursor.fetchall()
for x in myresult:
  print(x)

import mysql.connector
mydb = mysql.connector.connect(
  host="localhost",
  user="您的用户名",
  password="您的密码",
  database="我的数据库"
)
mycursor = mydb.cursor()
mycursor.execute("SELECT * FROM customers LIMIT 5 OFFSET 2")
myresult = mycursor.fetchall()
for x in myresult:
  print(x)

import mysql.connector
# 连接到MySQL数据库
mydb = mysql.connector.connect(
  host="localhost",
  user="yourusername",
  password="yourpassword",
  database="mydatabase"
)
# 创建游标对象
mycursor = mydb.cursor()
# 使用INNER JOIN合并用户和产品表格
sql = "SELECT \
  users.name AS user, \
  products.name AS favorite \
  FROM users \
  INNER JOIN products ON users.fav = products.id"
# 执行SQL查询
mycursor.execute(sql)
# 获取查询结果
myresult = mycursor.fetchall()
# 打印结果
for x in myresult:
  print(x)

sql = "SELECT \
  users.name AS user, \
  products.name AS favorite \
  FROM users \
  LEFT JOIN products ON users.fav = products.id"

sql = "SELECT \
  users.name AS user, \
  products.name AS favorite \
  FROM users \
  RIGHT JOIN products ON users.fav = products.id"