我找到了另一个答案，但不管用。这是我的密码：

import scrapy
import pymysql.cursors

# Connect to the database

connection = pymysql.connect(host='localhost',
                             user='root',
                             password='Kradz579032!!',
                             db='db',
                             charset='utf8mb4',
                             cursorclass=pymysql.cursors.DictCursor)

class QuotesSpider(scrapy.Spider):
    name = "quotes"

    def start_requests(self):
        urls = [
            'https://www.banggood.com/Wholesale-RC-Helicopter-c-264.html',
            'https://www.banggood.com/Wholesale-RC-Quadcopters-c-1848.html',
        ]
        for url in urls:
            yield scrapy.Request(url=url, callback=self.parse)

    def parse(self, response):
        for quote in response.css('.good_box_min'):
            yield {
                'producttitle': response.css('a.middle_product_text_170717::text').extract(),
                'productlink': response.css('a.middle_product_text_170717::attr(href)').extract(),
                'productprice': response.css('span.price.wh_cn::text').extract(),
                #'text': quote.css('span.text::text').extract_first(),
                #'author': quote.css('small.author::text').extract_first(),
                #'tags': quote.css('div.tags a.tag::text').extract(),
            }
        next_page = response.css('a#listNextPage::attr(href)').extract_first()
        if next_page is not None:
            next_page = response.urljoin(next_page)
            yield scrapy.Request(next_page, callback=self.parse)

    try:
        with connection.cursor() as cursor:

            sql = "INSERT INTO `banggood` (`producttitle`, `productlink`, `productprice`) VALUES (%s, %s, %s)"
            cursor.execute(sql, ('title', 'productlink', 'productprice'))

        connection.commit()

    finally:
        connection.close()

我不知道如何将所有零碎的数据插入mysql数据库。请告诉我如何用正确的方法做这件事。