一、查询数据库中的数据
1 #!/usr/bin/env python 2 # -*- coding: utf-8 -*- 3 4 import pymysql 5 6 #打开数据库连接 7 conn = pymysql.connect(host="localhost", user="root", password="admin@163.com", 8 port=3306, db="db1") 9 10 #使用cursor()方法获取操作游标 11 cursor = conn.cursor() 12 13 #查询操作 14 sql = "select * from tab1" 15 try: 16 cursor.execute(sql) #执行sql语句 17 18 results = cursor.fetchall() #获取查询的所有记录 19 print("id", "name", "email") 20 21 #遍历结果 22 for row in results: 23 id = row[0] 24 name = row[1] 25 email = row[2] 26 print(id, name, email) 27 except Exception as e: 28 raise e 29 30 finally: 31 cursor.close() #关闭游标 32 conn.close() #关闭连接
二、向数据库中插入数据
1 #!/usr/bin/env python 2 # -*- coding: utf-8 -*- 3 import pymysql 4 5 #连接数据库 6 conn = pymysql.connect(host="localhost", user="root", password="admin@163.com", 7 port=3306, db="db1") 8 9 #使用cursor()方法获取游标 10 cursor = conn.cursor() 11 12 sql_insert = """insert into tab1(nid, name, email) values (4, 'tt', 'tt@163.com')""" 13 14 try: 15 cursor.execute(sql_insert) 16 17 #提交数据 18 conn.commit() 19 20 except Exception as e: 21 #错误回滚 22 conn.rollback() 23 24 finally: 25 cursor.close() 26 conn.close()
三、更新数据库中的数据
1 #!/usr/bin/env python 2 # -*- coding: utf-8 -*- 3 import pymysql 4 5 #打开数据库连接 6 conn = pymysql.connect(host="localhost", user="root", password="admin@163.com", 7 port=3306, db="db1") 8 #使用cursor()方法获取操作游标 9 cursor = conn.cursor() 10 # 更新操作 11 sql_update = """update tab1 set email='yusheng_liang08@163.com' where nid='1'""" 12 13 try: 14 cursor.execute(sql_update) 15 16 conn.commit() 17 18 except Exception as e: 19 conn.rollback() 20 21 finally: 22 cursor.close() 23 conn.close()
四、删除数据库中的数据
1 #!/usr/bin/env python 2 # -*- coding: utf-8 -*- 3 import pymysql 4 5 #打开数据库连接 6 conn = pymysql.connect(host="localhost", user="root", password="admin@163.com", 7 port=3306, db="db1") 8 #使用cursor()方法获取操作游标 9 cursor = conn.cursor() 10 #删除操作 11 sql_delete = "delete from tab1 where name='tt'" 12 try: 13 14 cursor.execute(sql_delete) 15 conn.commit() #提交数据 16 17 except Exception as e: 18 conn.rollback() 19 20 finally: 21 cursor.close() 22 conn.close()