Python与Mysql交互实现增删改查基本操作

实现python与数据库的交互，你首先得先学习数据库的基本知识。以下代码照搬是实现不了这个功能的，具体情况自行解决。主要修改这些步骤（打开数据库连接，一：主机名，二：用户名，三：密码，四：数据库名称）

import pymysql

def main():
while True:
# 主菜单
temp = "数据库模块" \
"\n1.添加数据表" \
"\n2.删除数据表" \
"\n3.修改数据表" \
"\n4.查询数据表" \
"\n5.退出数据表"
print(temp)
# 用户输入序号
temp_num = int(input("序号："))

# 增
if temp_num == 1:
add("itcast", "chapter03", "yang")
# 删
elif temp_num == 2:
a1 = input("操作表名：")
drop("itcast", "chapter03", a1)
# 改
elif temp_num == 3:
a3 = input("原表名：")
a4 = input("新表名：")
delete("itcast", "chapter03", a3, a4)
# 查
elif temp_num == 4:
a2 = input("操作表名：")
select("itcast", "chapter03", a2)
# 退出
elif temp_num == 5:
break
else:
print("请输入正确序号")

def add(passwd, sql_name, table_name):
# 打开数据库连接，参数一：主机名，参数二：用户名，参数名：密码，参数四：数据库名称

db = pymysql.connect("localhost", "root", passwd, sql_name)

cursor = db.cursor()

sql = '''
create table books(id int(8) not null auto_increment,
name varchar(50) not null,
category varchar(50) not null,
price decimal(10, 2) default null,
publish_time date default null,
primary key(id)
)engine = MyISAM auto_increment = 1 default charset = utf8'''
sql = sql.replace("books", table_name)
cursor.execute(sql)
cursor.close()

def drop(passwd, sql_name, table_name):
# 打开数据库连接，参数一：主机名，参数二：用户名，参数名：密码，参数四：数据库名称

db = pymysql.connect("localhost", "root", passwd, sql_name)

cursor = db.cursor()

cursor.execute("drop table if exists " + table_name)

def delete(passwd, sql_name, table_name1, table_name2):
db = pymysql.connect("localhost", "root", passwd, sql_name)
cursor = db.cursor()

sql = "alter table 皮皮 rename LLL;"
sql = sql.replace("皮皮", table_name1)
sql = sql.replace("WWW", table_name2)
cursor.execute(sql)
cursor.close()

def select(passwd, sql_name, table_name):
# db = pymysql.connect("localhost", "root", passwd, sql_name)
# cursor = db.cursor()
#
# sql = """
# select * from books;
# """
# sql.replace("books", table_name)
#
# try:
#     cursor.execute(sql)
#     result = cursor.fetchmany()
#     for i in result:
#         id = i[0]
#         name = i[1]
#         category = i[2]
#         price = i[3]
#         publish_time = i[4]
#     print(id, name, category, price, publish_time)
# except:
#     print("出错")
#
# cursor.close()
db = pymysql.connect("localhost", "root", passwd, sql_name)

cursor = db.cursor()
sql = """
desc books;
"""
sql = sql.replace("books", table_name)
try:

cursor.execute(sql)
cursor.close()
while True:
result = cursor.fetchmany()
print(result)
if result == ():
break

except:
print("出错")

if __name__ == "__main__":
main()