python操作mysql数据库（增删改查）

1. 增加数据

import pymysql


# 1.连接MYSQL
conn = pymysql.connect(host="127.0.0.1", port=3306, user='root', passwd="root123", charset='utf8', db='unicom')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)

# 2.发送指令
sql = "insert into admin(username,password,mobile) value (%s, %s, %s)"
cursor.execute(sql, [username, password, mobile])
conn.commit()

# 3.关闭
cursor.close()
conn.close()
# create table admin(
#     id int not null auto_increment primary key,
#     username varchar(16) not null,
#     password varchar(64) not null,
#     mobile char(11) not null
# ) default charset=utf8;

2. 查询数据

import pymysql

# 1.连接MYSQL
conn = pymysql.connect(host="127.0.0.1", port=3306, user='root', passwd="root123", charset='utf8', db='unicom')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)

# 2.发送指令
cursor.execute("select * from admin")

# 获取第一条数据，字典
v1 = cursor.fetchone()

# 获取所有数据，列表套字典
v2 = cursor.fetchall()

# 3.关闭
cursor.close()
conn.close()
# create table admin(
#     id int not null auto_increment primary key,
#     username varchar(16) not null,
#     password varchar(64) not null,
#     mobile char(11) not null
# ) default charset=utf8;

3. 删除数据

import pymysql

# 1.连接MYSQL
conn = pymysql.connect(host="127.0.0.1", port=3306, user='root', passwd="root123", charset='utf8', db='unicom')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)

# 2.发送指令
cursor.execute("delete from admin where id = 4")
conn.commit()

# 3.关闭
cursor.close()
conn.close()
# create table admin(
#     id int not null auto_increment primary key,
#     username varchar(16) not null,
#     password varchar(64) not null,
#     mobile char(11) not null
# ) default charset=utf8;

4. 修改数据

import pymysql

# 1.连接MYSQL
conn = pymysql.connect(host="127.0.0.1", port=3306, user='root', passwd="root123", charset='utf8', db='unicom')
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)

# 2.发送指令
cursor.execute("update admin set mobile=%s where id=%s", ["18888888888", 5, ])
conn.commit()

# 3.关闭
cursor.close()
conn.close()
# create table admin(
#     id int not null auto_increment primary key,
#     username varchar(16) not null,
#     password varchar(64) not null,
#     mobile char(11) not null
# ) default charset=utf8;