psycopg2.errors.InFailedSqlTransaction：当前事务被中止，命令被忽略，直到事务块结束

我编写了一个 scrapy 程序来从站点抓取数据，如果我抓取到 json 文件或 csv 文件，该程序会成功抓取，当我尝试抓取到 postgres 数据库时会出现问题，下图显示了我收到的错误，我该如何修复错误：

def process_item(self, item, spider):
    """Save deals in the database.
    This method is called for every item pipeline component.
    """
    self.cur.execute("insert into Deals (Name,Deal_Url,Image_Url,Old_Price,Special_Price,Final_Price) values(%s,%s,%s,%s,%s,%s)",(item['Name'],item['Product_URL'],item['Image_URL'],item['Old_Price'],item['Special_Price'],item['Final_Price']))
    self.connection.commit()
    return item

当事务中的操作失败时，除了修复恶意操作（可能尝试访问中的任何值）之外，您还需要回滚item不存在）您可以将插入语句包装在 try/ except 块中：

def process_item(self, item, spider):
    """Save deals in the database.
    This method is called for every item pipeline component.
    """

    try:
        self.cur.execute("insert into Deals (Name,Deal_Url,Image_Url,Old_Price,Special_Price,Final_Price) values(%s,%s,%s,%s,%s,%s)",(item['Name'],item['Product_URL'],item['Image_URL'],item['Old_Price'],item['Special_Price'],item['Final_Price']))
        self.connection.commit()
    except:
        self.connection.rollback()
    return item