python操作三大主流数据库(2)python操作mysql②python对mysql进行简单的增删改查

python操作mysql②python对mysql进行简单的增删改查

1.设计mysql的数据库和表

id:新闻的唯一标示
title:新闻的标题
content:新闻的内容
created_at:新闻添加的时间
types:新闻的类型
image:新的缩略图
author:作者
view_count:浏览量
is_valid:删除标记

# 创建新闻数据库
create database news charset=utf8;

# 创建新闻表
create table news(
id int primary key auto_increment,
title varchar(200) not null,
content varchar(2000) not null,
types varchar(10) not null,
image varchar(300) null,
author varchar(20) null,
view_count int default 0,
created_at datetime null,
is_valid smallint default 1
) default charset="utf8";
'''

插入数据
INSERT INTO `news` VALUES ('1', '朝鲜特种部队视频公布 展示士兵身体素质与意志', '新闻内容', '推荐', '/static/img/news/01.png', null, '0', null, '1');
INSERT INTO `news` VALUES ('2', '男子长得像\"祁同伟\"挨打 打人者:为何加害检察官', '新闻内容', '百家', '/static/img/news/02.png', null, '0', null, '1');
INSERT INTO `news` VALUES ('3', '导弹来袭怎么办？日本政府呼吁国民堕入地下通道', '新闻内容', '本地', '/static/img/news/03.png', null, '0', null, '1');
INSERT INTO `news` VALUES ('4', '美监:朝在建能发射3发以上导弹的3000吨级新潜艇', '新闻内容', '推荐', '/static/img/news/04.png', null, '0', null, '1');
INSERT INTO `news` VALUES ('5', '证监会：前发审委员冯小树违法买卖股票被罚4.99亿', '新闻内容', '百家', '/static/img/news/08.png', null, '0', null, '1');
INSERT INTO `news` VALUES ('6', '外交部回应安倍参拜靖国神社:同军国主义划清界限', '新闻内容', '推荐', '/static/img/news/new1.jpg', null, '0', null, '1');
INSERT INTO `news` VALUES ('7', '\"萨德\"供地违法？韩民众联名起诉要求撤回供地', '新闻内容', '百家', '/static/img/news/new2.jpg', null, '0', null, '1');
INSERT INTO `news` VALUES ('10', '标题1', '新闻内容1', '推荐', '/static/img/news/01.png', null, '0', null, '1');

2.python简单操作mysql之数据库的连接和简单获取数据
#encoding:utf-8

import MySQLdb

'''
# 简单的连接
# 获取连接
conn = MySQLdb.connect(
host = '127.0.0.1',
user = 'root',
password = '',
db = 'news',
port = 3306,
charset = 'utf8'
)

# 获取数据
cursor = conn.cursor()
cursor.execute('select * from news order by created_at desc')
rest = cursor.fetchone()
print(rest)

# 关闭连接
conn.close()

3.python简单操作mysql之数据库的连接和简单获取数据改进之捕获异常

# 捕获异常
# 获取连接
try:
conn = MySQLdb.connect(
host = '127.0.0.1x',
user = 'root',
password = '',
db = 'news',
port = 3306,
charset = 'utf8'
)

# 获取数据
cursor = conn.cursor()
cursor.execute('select * from news order by created_at desc')
rest = cursor.fetchone()
print(rest)

# 关闭连接
conn.close()
except MySQLdb.Error as e:
print('mysql error:%s' % e)

4.python简单操作mysql之数据库的连接和单获取所有数据
# 获取连接
try:
conn = MySQLdb.connect(
host = '127.0.0.1',
user = 'root',
password = '',
db = 'news',
port = 3306,
charset = 'utf8'
)

# 获取数据
cursor = conn.cursor()
cursor.execute('select * from news')
rows = cursor.fetchall()
print(cursor.description)

for row in rows:
print(row)

# 关闭连接
conn.close()
except MySQLdb.Error as e:
print('mysql error:%s' % e)

5.python简单操作mysql之数据库的操作类

class MysqlConnection(object):

# 初始化
def __init__(self, host = '127.0.0.1', port = 3306, user = 'root', password = '', db = 'news',charset='utf8'):
self._host = host
self._port = port
self._user = user
self._password = password
self._db = db
self._charset = charset
self._conn = None
self._cursor = None
self.get_conn()

# 关闭数据库连接
def close(self):
if self._cursor:
self._cursor.close()
self._cursor = None

if self._conn:
self._conn.close()
self._conn = None

def commit(self):
self._conn.commit()

# 获取数据库连接
def get_conn(self):
try:
self._conn = MySQLdb.connect(
host = self._host,
user = self._user,
password = self._password,
db = self._db,
port = self._port,
charset = self._charset
)

self._cursor = self._conn.cursor()
except MySQLdb.Error as e:
print('mysql error:%s' % e)

# 获取单条新闻
def get_one(self):

sql = 'select * from news where types = %s order by created_at desc'
# 获取数据
self._cursor.execute(sql,('百家',))
rest = dict(zip([k[0] for k in self._cursor.description], self._cursor.fetchone()))

# 关闭连接
self.close()
return rest

# 获取多条新闻
def get_more(self):

sql = 'select * from news where types = %s order by created_at desc'
# 获取数据
self._cursor.execute(sql,('百家',))
rest = [dict(zip([k[0] for k in self._cursor.description], row))
for row in self._cursor.fetchall()]

# 关闭连接
self.close()
return rest

def add_one(self):
sql = 'insert into news(title,image,content,types,is_valid) values(%s, %s, %s, %s, %s)'
self._cursor.execute(sql, ('标题1','/static/img/news/01.png', '新闻内容1','推荐',1))
self.commit()
self.close()

def main():
obj = MysqlConnection()
# rst = obj.get_more()
# rst = obj.get_one()
# print(rst)
obj.add_one()

if __name__ == "__main__":
main()