insert
# insert :插入语句
import pymysql
def main():
no = int(input('请输入部门编号：'))
name = input('请输入名字：')
loc = input('请输入所在地：')
#1. 创建数据库连接对象
con = pymysql.connect(host='120.78.202.21', port=3306,database='hrs',
charset='utf8', user='root', password='123456') # autocommit = on/off 自动提交功能的开启和关闭
try:
#2. 通过连接对象拿到游标
with con.cursor() as cursor:
#3. 通过游标执行SQL并获得执行结果
result = cursor.execute(
# %s ：安全占位符（security）
'insert into tb_dept values (%s,%s,%s)',
(no, name, loc)
)
if result == 1:
#4. 提交事务
con.commit()
print("添加成功！")
except:
#4. 操作失败回滚事务
con.rollback()
finally:
# 5. 无论成功还是失败，关闭连接
con.close()
print(con)
if __name__ == '__main__':
main()delete
# delete ：删除语句
import pymysql
def main():
no = int(input('请输入部门编号：'))
#1. 创建数据库连接对象
con = pymysql.connect(host='120.78.202.21',port=3306,database='hrs',
charset='utf8',user='root',password='123456') # autocommit = Ture/Flase 自动提交功能的开启和关闭
try:
#2. 通过连接对象拿到游标
#with ：在离开这个代码段后，自动释放游标
with con.cursor() as cursor:
#3. 通过游标执行SQL并获得执行结果
result = cursor.execute(
# %s ：安全占位符（security）
'delete from tb_dept where dno=%s',
(no, )
)
if result == 1:
#4. 提交事务
con.commit()
print("删除成功！")
except:
#4. 操作失败回滚事务
con.rollback()
finally:
# 5. 无论成功还是失败，关闭连接
con.close()
if __name__ == '__main__':
main()update
"""
更新数据库数据
"""
import pymysql
def main():
"""主函数：程序入口"""
dept_no = int(input('请输入部门编号：'))
name = input('请输入名字：')
loc = input('请输入所在地：')
#1. 创建数据库连接对象
con = pymysql.connect(host='120.78.202.21', port=3306, database='hrs',
charset='utf8', user='root', password='123456')# autocommit = on/off 自动提交功能的开启和关闭
try:
#2. 通过连接对象拿到游标
with con.cursor() as cursor:
#3. 通过游标执行SQL并获得执行结果
result = cursor.execute(
# %s ：安全占位符（security）
'update tb_dept set dname=%s, dloc=%s where dno=%s',
(name, loc, dept_no,)
)
if result == 1:
#4. 提交事务
con.commit()
print("更新成功！")
except:
#4. 操作失败回滚事务
con.rollback()
finally:
# 5. 无论成功还是失败，关闭连接
con.close()
if __name__ == '__main__':
main()select
"""
导入pymysql模块
"""
import pymysql
from pymysql.cursors import DictCursor
def main():
"""主函数：程序入口"""
#1. 创建数据库连接对象
con = pymysql.connect(host='120.78.202.21', port=3306,
database='hrs', charset='utf8',
user='root', password='123456')
# autocommit = on/off 自动提交功能的开启和关闭
try:
#2. 通过连接对象拿到游标
with con.cursor(cursor=DictCursor) as cursor:
#3. 通过游标执行SQL并获得执行结果
cursor.execute('select dno as no, dname as name, dloc as loc from tb_dept')
print('编号\t名称\t所在地')
for dept in cursor.fetchall():
print(dept['no'], end='\t')
print(dept['name'], end='\t')
print(dept['loc'])
except:
#4. 操作失败回滚事务
con.rollback()
finally:
# 5. 无论成功还是失败，关闭连接
con.close()
if __name__ == '__main__':
main()select方法二
"""
导入pymysql模块
"""
import pymysql
from pymysql.cursors import DictCursor
class Dept():
def __init__(self, no, name, loc):
self.no = no
self.name = name
self.loc = loc
def __str__(self):
return f'{self.no}\t{self.name}\t{self.loc}'
def main():
"""主函数：程序入口"""
#1. 创建数据库连接对象
con = pymysql.connect(host='120.78.202.21', port=3306,
database='hrs', charset='utf8',
user='root', password='123456')
# autocommit = on/off 自动提交功能的开启和关闭
try:
#2. 通过连接对象拿到游标
with con.cursor(cursor=DictCursor) as cursor:
#3. 通过游标执行SQL并获得执行结果
cursor.execute('select dno as no, dname as name, dloc as loc from tb_dept')
print('编号\t名称\t所在地')
for result in cursor.fetchall():
dept=Dept(**result)
print(dept)
except:
#4. 操作失败回滚事务
con.rollback()
finally:
# 5. 无论成功还是失败，关闭连接
con.close()
if __name__ == '__main__':
main()