Pymysql-总结

背景：工作需要大量链接数据库进行一些操作查询，但是也会有出现异常情况

1.添加字段

1 ALTER TABLE app01_student ADD COLUMN Relation VARCHAR(255) DEFAULT'无';

2 、D:\Users\zhang.ning\PycharmProjects\APP>python manage.py startapp app01

　　

2.查询操作

import pymysql

sql = "SELECT * FROM userinfo "

def Sql_Query():
    try:
        connection = pymysql.connect(host='127.0.0.1',
                                     user='root',
                                     password='123456',
                                     db='test',
                                     charset='utf8',
                                     port=3306
                                     )
    except Exception as e:
        print(e)
        exit()
    try:
        with connection.cursor() as cursor:
            cursor.execute(sql)
            result = cursor.fetchall()
    except Exception as e:
        print(e)
        return False, None
    else:
        return True, result
    finally:
        connection.close()

if __name__ == '__main__':
    flag, rs = Sql_Query()
    if flag:
        print(rs)
    else:
        print("NO")