import pymysql 导入pymysql 数据库
1 链接数据库服务器
db=pymysql.connect (host='localhost',user='root',password='123456')
print(db)
2 选中数据库
db.select_db('data1')
3 设置字符集
db.set_charset('utf8')
4创建游标对象
cursor=db.cursor(cursor=pymysql.cursor.DictCursor)
5 准备sql语句
sql='select * from star'
6执行sql语句
rowcount=cursor.execute(sql)
print(rowcount)
7 关闭游标对象
cursor.close()
8 关闭数据库链接
db.close()
案例说明
请写出使用pymysql操作MySQL进行转账的操作,要求id为1的用户向id为2的用户转账200元,如果转账过程发生异常,则回滚转账 操作
import pymysql
acount=pymysql.connect(host='localhost',user='root',password='123456',database='data1',chaeset='utf8')
cursor=acount.cursor()
sql1='updata account set banlance=banlance-200 where id =%d'
sql2='updata account set banlance=banlance+200 where id =%d'
try:
cursor.execute(sql1%1)
cursor.execute(sql2%2)
acount.commit()
print("转账成功")
except Exception as e;
print(e)
acount.rollback()
print("机器故障,转账失败")
finally:
sursor.close()
acount.close()