Python——Mysql

一、导入　　

        import pymysql

二、连接

def connect_wxremit_db():
    return pymysql.connect(host='10.123.5.28',
                           port=3306,
                           user='root',
                           password='root1234',
                           database='db_name',
                           charset='latin1')
'''
hots:主机地址
port:端口号
user:用户
password：密码
database：数据库
charset：表
'''

三、查询

def query_country_name(cc2):
    sql_str = ("SELECT Fcountry_name_zh"
                + " FROM t_country_code"
                + " WHERE Fcountry_2code='%s'" % (cc2))
    logging.info(sql_str) #将内容写入日志

    con = mysql_api.connect_wxremit_db() #执行连接数据库
    cur = con.cursor()  #使用cursor()方法获取操作游标
    cur.execute(sql_str) #使用execute方法执行SQL语句
    rows = cur.fetchall()#接收全部的返回结果行.
    cur.close()
    con.close()

    assert len(rows) == 1, 'Fatal error: country_code does not exists!'
    return rows[0][0]

四、插入

def insert_file_rec(self, file_name, file_md5):
        #连接数据库
        con = mysql_api.connect_wxremit_db()
        #获取操作游标
        cur = con.cursor()
        try:
            #SQL语句
            sql_str = ("INSERT INTO t_forward_file (Ffile_name, Ffile_md5)",
                       + " VALUES ('%s', '%s')" % (file_name, file_md5))
            #执行SQL语句
            cur.execute(sql_str)
            #提交到数据库
            con.commit()
        except:
            #插入数据失败
            con.rollback()
            #写入日志
            logging.exception('Insert operation error')
            #当程序出现错误，通过raise显示地引发异常。后面的语句将不能执行
            raise
        finally:
            cur.close()
            con.close()

五、批量插入

remit_ids = [('', 'CAD'), ('', 'HKD')]

con = mysql_api.connect_wxremit_db()
        cur = con.cursor()
        try:
                cur.executemany("INSERT INTO t_order (Fremit_id, Fcur_type, Fcreate_time"
                                                + " VALUES (%s, %s, now())", new_items)
                assert cur.rowcount == len(remit_ids), 'my error message'
                con.commit()
        except Exception as e:
                con.rollback()
                logging.exception('Insert operation error')
        finally:
                cur.close()
                con.close()

六、更新

def update_refund_trans(self, remit_id):
        con = mysql_api.connect_wxremit_db()
        cur = con.cursor()
        try:
            sql_str = ("SELECT Fremit_id"
                       + " FROM t_wxrefund_trans"
                       + " WHERE Fremit_id='%s'" % remit_id
                       + " FOR UPDATE")
            logging.info(sql_str)

            cur.execute(sql_str)
            assert cur.rowcount == 1, 'Fatal error: The wx-refund record be deleted!'

            sql_str = ("UPDATE t_wxrefund_trans"
                        + " SET Fcheck_amount_flag=1"
                        + ", Fmodify_time=now()"
                        + " WHERE Fremit_id='%s'" % remit_id
            logging.info(sql_str)
            cur.execute(sql_str)

            assert cur.rowcount == 1, 'The number of affected rows not equal to 1'
            con.commit()
        except:
            con.rollback()
            logging.exception('Update operation error')
            raise
        finally:
            cur.close()
            con.close()

七、删除

sql = "DELETE FROM EMPLOYEE WHERE AGE > %s" % (20)