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why python raise a error ：“float argument required, not unicode”

for each_ID ,each_Title in zip(Id,Title):
url="http://www.zjjsggzy.gov.cn/%E6%96%B0%E6%B5%81%E7%A8%8B/%E6%8B%9B%E6%8A%95%E6%A0%87%E4%BF%A1%E6%81%AF/jyxx_1.html?iq=x&type=%E6%8B%9B%E6%A0%87%E5%85%AC%E5%91%8A&tpid=%s&tpTitle=%s"%(each_ID,each_Title)
“each_ID”and “each_Title” are from website unicode parameters, but why it cause a “float”error, %s is not a string?

You have loads of % formatters in your string. %E formats a float object. You have several of those in your string, including at the start:
"http://www.zjjsggzy.gov.cn/%E6
# ^^
You'd need to double up every single % used in a URL character escape:
"http://www.zjjsggzy.gov.cn/%%E6%%96%%B0%%E6%%B5%%81%%E7%%A8%%8B/..."
That'd be a lot of work, you'd be better off using a different string formatting style. Use str.format():
url = (
"http://www.zjjsggzy.gov.cn/"
"%E6%96%B0%E6%B5%81%E7%A8%8B/%E6%8B%9B%E6%8A%95%E6%A0%87%E4%BF%A1%E6%81%AF"
"/jyxx_1.html?iq=x&type=%E6%8B%9B%E6%A0%87%E5%85%AC%E5%91%8A&"
"tpid={}&tpTitle={}".format(
each_ID, each_Title)
)
I broke the string up into multiple chunks to make it easier to read; the {} brackets delineate the placeholders.

Try using the format method on string. The existing '%' chars conflicting with your %s placeholders :
for each_ID ,each_Title in zip(Id,Title):
url="http://www.zjjsggzy.gov.cn/%E6%96%B0%E6%B5%81%E7%A8%8B/%E6%8B%9B%E6%8A%95%E6%A0%87%E4%BF%A1%E6%81%AF/jyxx_1.html?iq=x&type=%E6%8B%9B%E6%A0%87%E5%85%AC%E5%91%8A&tpid={}&tpTitle={}".format(each_ID, each_Title)

Replace a double backslash with a single backslash in a string in python

I know that variants of this topic have been discussed elsewhere, but none of the other threads were helpful.
I want to hand over a string from python to sql. It might however happen that apostrophes (') occur in the string. I want to escape them with a backslash.
sql = "update tf_data set authors=\'"+(', '.join(authors).replace("\'","\\\'"))+"\' where tf_data_id="+str(tf_data_id)+";"
However, this will always give \\' in my string. Therefore, the backslash itself is escaped and the sql statement doesn't work.
Can someone help me or give me an alternative to the way I am doing this?
Thanks

Simply don't.
Also don't concatenate sql queries as these are prone to sql injections.
Instead, use a parameterized query:
sql = "update tf_data set authors=%(authors)s where tf_data_id=%(data_id)s"
# or :authors and :data_id, I get confused with all those sql dialects out there
authors = ', '.join(authors)
data_id = str(tf_data_id)
# db or whatever your db instance is called
db.execute(sql, {'authors': authors, 'data_id': data_id})

You're using double-quoted strings, but still escaping the single quotes within them. That's not required, all you need to do is escape the backslash that you want to use in the replace operation.
>>> my_string = "'Hello there,' I said."
>>> print(my_string)
'Hello there,' I said.
>>> print(my_string.replace("'", "\\'"))
\'Hello there,\' I said.
Note that I'm using print. If you just ask Python to show you its representation of the string after the replace operation, you'll see double backslashes because they need to be escaped.
>>> my_string.replace("'", "\\'")
"\\'Hello there,\\' I said."

As others have alluded to, if you are using a python package to execute your SQL use the provided methods with parameter placeholders(if available).
My answer addresses the escaping issues mentioned.
Use a String literal with prefix r
print(r"""the\quick\fox\\\jumped\'""")
Output:
the\quick\fox\\\jumped\'

Format string with regex in args in Python

I am trying to create a string in Python using the format method, but one of the arguments is a regular expression. I tried:
>>> 'foo{}bar'.format('[\s]+')
'foo[\\s]+bar'
Because of the escaping, I can't use the result as a re.search pattern. Is there a way not to escape it?
Thanks.

In fact, you don't need to do anything, because the result is what you expect. foo[\\s]+bar is the representation, but not the real value, which is foo[\s]+bar. Try this:
>> print 'foo{}bar'.format('[\s]+')
# and you will get
>> 'foo[\s]+bar'

Escape from html %20

I'm working on something in Python and I need to escape from %20, the space in a URL. For example:
"%20space%20in%20%d--" % ordnum
So I need to use %20 for a URL but then %d for a number. But I get this error:
TypeError: not enough arguments for format string
I know what the problem is I just don't know how to escape from a %20 and fix it.

One way would be to double the % characters:
"%%20space%%20in%%20%d--" % ordnum
but a probably better way is using urllib.quote_plus():
urllib.quote_plus(" space in %d--" % ordnum)

The %20 should look like %%20 when Python's formatter sees it. To Python, %% formats out to %.

>>> import urllib
>>> unquoted = urllib.unquote("%20space%20in%20%d--")
>>> ordnum = 15
>>> print unquoted % ordnum
space in 15--

I see three ways to solve this:
Escape the %.
"%%%20dogs" % 11
Use the new .format syntax.
"{}%20dogs".format(11)
Use the + sign instead of %20, as I think that's possible as well.
"%+dogs" % 11

How can I replace double and single quotations in a string efficiently?

I'm parsing a xml file and inserting it into database.
However since some text containes double or single quotation I'm having problem with insertion. Currently I'm using the code shown below. But it seems it's inefficient.
s = s.replace('"', ' ')
s = s.replace("'", ' ')
Is there any way I can insert text without replacing these quotations?
OR
Is there any efficient way to substitute them efficiently ?
Thanks !

Why can't you insert strings containing quote marks into your database? Is there some weird data type that permits any character except a quote mark? Or are you building an insert statement with literal strings, rather than binding your strings to query parameters as you should be doing?
If you're doing
cursor.execute('insert into mytable (somefield) values ("%s")' % (mystring))
then that's unsafe and wrong. Instead, you should be doing
cursor.execute('insert into mytable (somefield) values (%(myparam)s)',
dict(myparam=mystring))

you should use str.translate instead of doing two replace() calls
>>> import string
>>> quotes_to_spaces=string.maketrans('"\''," ")
>>> s=s.translate(quotes_to_spaces)

You could try something like _mysql.escape_string():
>>> import _mysql
>>> a = '''I said, "Don't do that"'''
>>> a
'I said, "Don\'t do that"'
>>> _mysql.escape_string(a)
'I said, \\"Don\\\'t do that\\"'
However, the manual recommends using connection.escape_string(), but I think you need a database connection first.