sql语句中单引号和反引号的区别？
网上说Mysql中字段跟保留字相同时用反引号（键盘中ESC键下面那个）。但是我的字段跟保留字不一样，用单引号就报错，改成反引号就正确了，为什么啊？？？？？
我把存储到数据库的完整代码贴出来（创建表非手动，用代码实现的），这个代码能正确运行，请高手看看为什么非要用反引号呢？？？？
# wiki.py
from urllib.request import urlopen
from bs4 import BeautifulSoup
import re
import pymysql.cursors
resp = urlopen("https://en.wikipedia.org/wiki/Main_Page").read().decode("utf-8")
soup = BeautifulSoup(resp, "html.parser")
listUrls = soup.findAll("a", href=re.compile("^/wiki/"))
for url in listUrls:
if not re.search("\.(jpg|JPG)$", url["href"]):
urlname = url.get_text()
urlhref = "https://en.wikipedia.org" + url["href"]
print(urlname, "---> ", urlhref)
# 获取数据库链接
connection = pymysql.connect(host="localhost",
user="root",
password="admin",
db="wikiurl",
charset="utf8mb4")
try:
# 获取会话指针
with connection.cursor() as cursor:
# 如果不存在就创建表，字段用反单引号！！！
sql_create_table = '''CREATE TABLE IF NOT EXISTS `urls` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`urlname` varchar(255) NOT NULL,
`urlhref` varchar(1000) NOT NULL,
PRIMARY KEY (`id`))ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin AUTO_INCREMENT=1'''
cursor.execute(sql_create_table)
# 创建sql语句
sql_insert = 'insert into urls (urlname, urlhref) values (%s, %s)'
# 执行sql 语句
cursor.execute(sql_insert, (urlname, urlhref))
# 提交
connection.commit()
finally:
connection.close()
