我在一个刮擦爬虫工作，这个问题真的困扰我，因为我已经被困在这几天了。
当我对sqlite db使用“？”而不是“%s”时，此占位符函数可以正常工作。但是当使用“？”作为数据库切换到mysql时，它显示：
“typeerror:在字符串格式化过程中并非所有参数都已转换”
即使我花了很多精力修改代码和更改占位符（应该是？），它仍然显示：
“query=query%self.\u escape\u args（args，conn）valueerror:不支持格式字符'，'”
更具体地说：

Traceback (most recent call last):

  File "/usr/lib64/python3.4/dist-packages/twisted/internet/defer.py", line 653, in _runCallbacks
    current.result = callback(current.result, *args,**kw)

File "/home/ec2-user/lulu_testing/get_download_file/hello_scrapy/hello/hello/pipelines.py", line 42, in process_item
    self.cur.execute(insert_query, insert_values)

File "/usr/lib/python3.4/dist-packages/pymysql/cursors.py", line 163, in execute
    query = self.mogrify(query, args)

File "/usr/lib/python3.4/dist-packages/pymysql/cursors.py", line 142, in mogrify
    query = query % self._escape_args(args, conn)

ValueError: unsupported format character ',' (0x2c) at index 94

mysql版本的管道

import pymysql
import scrapy
from hello.items import HelloItem

class HelloPipeline(object):

def __init__(self):#

    self.conn = pymysql.connect(host="localhost", port=3306, user="root", passwd="lulu", db="test", charset="utf8", use_unicode=True)
    self.cur = self.conn.cursor()

    self.cur.execute("drop table IF EXISTS test;")
    self.conn.commit()

    self.cur.execute("create table if not EXISTS table_test_4(test0 text, test1 text, test2 text, test3 text,test4 text, test5 text, test6 text, test7 text, test8 text, test9 text);")
    self.conn.commit()

    #pass

def process_item(self, item, spider):#

    col = ",".join(item.keys())
    placeholders = ",".join(len(item) * "%s")

    insert_query = "INSERT INTO test_table_4({0}) VALUES({1});".format(col,placeholders)

    insert_values = tuple(item.values())

    self.cur.execute(insert_query, insert_values)

    return item

def close_spider(self, spider):#
    self.cur.close()
    self.conn.close()
    #pass

sqlite版本（我使用的是b4）

import sqlite3
import scrapy
from hello.items import HelloItem

class HelloPipeline(object):

def open_spider(self, spider):#
    self.conn = sqlite3.connect("test_database_ver_2018_03_31.sqlite")
    self.cur = self.conn.cursor()
    self.cur.execute("create table if not exists test_table(test0 text, test1 text, test2 text, test3 text,test4 text, test5 text, test6 text, test7 text, test8 text, test9 text);")        
    #pass

def close_spider(self, spider):#
    self.conn.commit()
    self.conn.close()
    #pass

def process_item(self, item, spider):#

    col = ",".join(item.keys())       
    placeholders = ",".join(len(item) * "?")
    sql = "insert into test_table({}) values({})"

    self.cur.execute(sql.format(col, placeholders), tuple(item.values()))

    return item

爬行器主程序的数据设置

testitem = HelloItem()

    testitem["test0"] = house_detail.select(".houseInfoTitle")[0].text        
    testitem["test1"] = house_detail.select(".pageView")[0].text 
    testitem["test2"] = house_detail.select(".detailInfo")[0].text
    testitem["test3"] = house_detail.select(".houseIntro")[0].text
    testitem["test4"] = house_detail.select(".lifeBox")[0].text
    testitem["test5"] = house_detail.select(".labelList")[0].text
    testitem["test6"] = house_detail.select(".facility")[0].text
    testitem["test7"] = str(house_detail.select(".userInfo"))
    testitem["test8"] = str(house_detail.select(".banner"))
    testitem["test9"] = str(house_detail.select("#show"))

    return testitem

项目设置

import scrapy

class HelloItem(scrapy.Item):

test0 = scrapy.Field()
test1 = scrapy.Field()
test2 = scrapy.Field()
test3 = scrapy.Field()
test4 = scrapy.Field()
test5 = scrapy.Field()
test6 = scrapy.Field()
test7 = scrapy.Field()
test8 = scrapy.Field()
test9 = scrapy.Field()