flask-mysql编程错误：字符串格式化期间并非所有参数都已转换

Question

I am trying to make a simple program using flask + mysql. I just receive two arguments in a POST and write to the database:

@app.route('/upd',methods=['POST'])
def upd():
   _lat = request.form['lat']
   _lng = request.form['lng']

   cur = mysql.connection.cursor()
   cur.execute('insert into locations(lat,lng) values (?,?)',(_lat,_lng,))
   cur.commit()

   return jsonify(request.form)

The problem is that when i try to post the data from the client , i am getting:

ProgrammingError: not all arguments converted during string formatting
127.0.0.1 - - [28/Apr/2018 23:46:14] "POST /upd HTTP/1.1" 500 -

If i comment the SQL statement, the client will receive the output of jsonify which looks correct:

{
"lat": "3.2001",
"lng": "-11.45465"
}

Answer 1

You need to specify variables using %s or %(name)s parameter style, according to the docs :

The parameters found in the tuple or dictionary params are bound to the variables in the operation. Specify variables using %s or %(name)s parameter style (that is, using format or pyformat style).

cur.execute('insert into locations(lat,lng) values (%s,%s)' % (_lat,_lng,))

should work.