第四篇：python操作数据库时的传参问题

python在操作数据库执行sql的时候我们经常会遇到传参问题，以下是我总结的几种方法：

1、格式化字符串

city = 'beijing'
cur.execute(“SELECT * FROM %s WHERE city = %s”, city)

2、使用字典传递

sql = “INSERT INTO user VALUES(%(username)s, %(password)s, %(email)s)”
value = {“username”:zhangsan,“password”:123456,“email”:123456@ouvps.com}
cur.execute(sql, value)

3、传递参数+参数名称：利用‘三引号’实现复杂SQL的换行，然后对参数进行拼接，如下样例中的time，根据自己的情况而定

def sql_func(time):
    time = "'" + time + "'"
    fail_sql='''
    SELECT substr(s_start_time,1,10)  "日期",count(*)  "失败数量"
      FROM T_SG_WS_EXE_LOG L
     WHERE 1 = 1
       AND (S_WS_METHOD = 'NotifyOrderStatus' OR (S_WS_METHOD = 'placeOrder' AND S_IS_OK = 'false'))
    and s_request_str not like  '%"deployStatus":"2120"%' and s_request_str not like  '%"deployStatus":"0"%'
    and  substr(s_start_time,1,10) = '''+time +'''group by substr(s_start_time,1,10) 
    '''
    # 使用cursor进行各种操作
    y=cr.execute(fail_sql)
    result = y.fetchall()
    return result

参考文档：https://www.cnblogs.com/goodhacker/p/3257882.html