You're solution opens you up to SQL injections. If you read the first section of the documentation, it specifically says not to do it the way you are proposing:

Never do this -- insecure!

symbol = 'RHAT'
c.execute("SELECT * FROM stocks WHERE symbol = '%s'" % symbol)

Do this instead

t = ('RHAT',)
c.execute('SELECT * FROM stocks WHERE symbol=?', t)

So you should change your code to something along the following lines:

conn = sqlite3.connect('connex.db')
cur = conn.cursor()
mobileval = '0400-123-456'
emailval = '[email protected]'
constrain = 4

q = "UPDATE licontacts310317 SET (?, ?) 
             WHERE (?)=(?)"

cur.execute(q, (liemailval, limobileval, id, constrain) )

conn.commit()
conn.close()

I haven't tested it, but hopefully you get the idea =)

The following works: Its just standard SQL at this point.

cur.execute("""UPDATE table_name1
            SET email = '[email protected]', phone = '0400-123-456'
            WHERE id = 4""")

I was facing a similar issue with my own code and was able to get my code working using the following:

cur.execute("UPDATE licontacts310317 SET liemail=?, limobile=? WHERE id=? ", (liemailval, limobileval, constrain))

Someone else already commented this, but it's better to use the ? placeholder and not the string formatting operations because those leave your db vulnerable to SQL injection attacks (basically, hackers).

OK. I made a solution that works with parameters.

First thanks to David for his original answer. It had a small syntax error (corrected in the comments for that answer) but it was enough to help me work out how to get it working without parametising.

(Note:I think David posted his reply before I edited the question to add the need to working with parameters.)

Then this answer helped me parametise the solution.

Here is my solution to the question. I'm poting it in case someone else has the same problem because I did quite a bit of searching before posting the original question and couldn't find the answer.

conn = sqlite3.connect('connex.db')
cur = conn.cursor()
mobileval = '0400-123-456'
emailval = '[email protected]'
constrain = 4

cur.execute("UPDATE licontacts310317 SET liemail=%s, limobile=%s 
             WHERE %s=?" % (liemailval, limobileval, id), (constrain,))

conn.commit()
conn.close()

Use Dictionaries!

They seem to work well:

cur.execute(
   """UPDATE table_name1 
      SET email =:email, 
      phone =:phone 
      WHERE id = 4
   """, 
   {"email": "[email protected]", "phone": '0400-123-456'}
)

So you can just post a dictionary in like so, provided they contain the keys:

cur.execute(
   """UPDATE table_name1 
      SET email =:email, 
      phone =:phone 
      WHERE id = 4
   """, 
   the_dictionary
)

Where the_dictionary = {"email": "[email protected]", "phone": "0400-123-456"}. You can put in as many as you'd like. This seems more readable as well I feel.