'''
fetchone()执行查询语句时，获取查询结果的第一个数据，返回一个元组
fetchall()执行查询时，获取结果集的所有行，一行构成一个元组，再将这
元组，再将这些元组装入一个元组返回
使用python连接数据库
'''
# from pymysql import *
#
# try:
# conn = connect(
# host='localhost',
# port=3306,
# db='python03',
# user='root',
# passwd='root',
# charset='utf8'
# )
# cursor = conn.cursor()
# cursor.execute('select * from students;')
# result = cursor.fetchone
# cursor.close()
# conn.close()
# except Exception as e:
# print('Error %d:%s'%(e.args[0],e.args[1]))
#
**封装MySQL-DB类**
from pymysql import *
class MyDb(object):
def __init__(self):
self.conn()
def conn(self):
try:
self.conn = connect(
host='127.0.0.1',
port=3306,
user='root',
passwd='root',
db = 'python03',
charset='utf8'
)
except Exception as e:
print(e)
def get_one(self):
sql = 'select * from students'
# 获取游标
cursor = self.conn.cursor()
# 执行SQL语句
cursor.execute(sql)
# 获取执行结果
result = cursor.fetchone()
print(result)
cursor.close()
# self.conn.close()
return result
def get_more(self):
sql = 'select * from students'
# 获取游标
cursor = self.conn.cursor()
# 执行SQL语句
cursor.execute(sql)
# 获取执行结果
result = cursor.fetchall()
# print(result)
cursor.close()
# self.conn.close()
return result
# def close_conn(self):
# self.conn.close()
def __del__(self):
self.conn.close()
def main():
obj = MyDb()
res = obj.get_more()
# obj.get_one()
for item in res:
print(item)
if __name__ == '__main__':
main()
