根据网上的例子用flask做一个销售管理系统，页面上输入数据后没有导入到数据库中

网页代码

        <div>
            <form action = "{{ url_for('addrec') }}" method = "POST">
             <h3>进货登记</h3>

             商品名<br>
             <input type = "text" name = "gname" /></br>

             生产厂家<br>
             <input type = "text" name = "fname" ><br>

             型号<br>
             <input type = "text" name = "type" /><br>

             单价<br>
             <input type = "text" name = "price" /><br>

             数量<br>
             <input type = "text" name = "num" /><br>

             总金额<br>
             <input type = "text" name = "sum" /><br>
             进货日期<br>
             <input type = "text" name = "inyear" />年 

             <input type = "text" name = "inmonth" />月

             <input type = "text" name = "inday" />日<br>

             业务员编号<br>
             <input type = "text" name = "eno" /><br>
             <br>
             <input type = "submit" value = "添加入库" /><br>
          </form>
        </div>

app.py

from flask import Flask, render_template, url_for,request
import sqlite3 as sql
import sqlite3

DEBUG = True
app = Flask(__name__)


#连接html文件
@app.route('/')
def home():
   return render_template('sell_head.html')

@app.route('/ingood')
def new_good():
   return render_template('sell_in.html')

@app.route('/addrec',methods = ['POST', 'GET'])
def addrec():
   if request.method == 'POST':
      try:
         gname = request.form['gname']
         factory = request.form['fname']
         type = request.form['type']
         price = request.form['price']
         num = request.form['num']
         sum = request.form['sum']
         inyear = request.form['inyear']
         inmonth = request.form['inmonth']
         inday = request.form['inday']
         eno = request.form['eno']

         with sql.connect("sell_system.db") as con:
            cur = con.cursor()

            cur.execute("INSERT INTO good (gname,factory,type,price,num,sum,inyear,inmonth,inday,eno)VALUES (?,?,?,?,?,?,?,?,?,?)",(gname,fname,type,price,num,sum,inyear,inmonth,inday,eno) )

            con.commit()
            msg = "Record successfully added"
      except:
         con.rollback()
         msg = "error in insert operation"

      finally:
         return render_template("result.html",msg = msg)
         con.close()

输入进货登记的数据后点击添加入库，跳转页面 error in insert operation
到底是哪里出问题了