title: Error while inserting data : cx_Oracle.DatabaseError: ORA-01722: invalid number
body: <p>I need to insert data into customer table</p>
  
  <pre><code>cur.execute(''' 
  CREATE TABLE customer (customerId varchar(20),customerName 
  varchar(20),telephoneNo int,
                          addressId int, customerType varchar(20),
                          discount int, memCardType varchar(20))''')
  class customer:
      def __init__(self,customername,telephonenumber,addressid):
          self.customername=customername
          self.telephonenumber=telephonenumber
          self.addressid=addressid
          id=4
          t='a'
  
          cur.execute("INSERT INTO customer VALUES (:1,:2,:3,:4,:5,:6,:7)", 
     (id,customername,telephonenumber,addressid,t,id,t))
          cur.execute("SELECT * FROM customer")
          print(cur.fetchall())`
  if(ch==1):
  nm = input("name:")
  tel = input("number:")
  add = input("address")
  customer(nm,tel,add)
  </code></pre>
  
  <p>Error: here choice is being stored in variable ch, and if ch is 1 the data are being asked by user and data is stored in the table</p>
  
  <pre><code>Traceback (most recent call last):
  
  customer(nm,tel,add)
  line 23, in __init__
  cur.execute("INSERT INTO customer VALUES (:1,:2,:3,:4,:5,:6,:7)",(id,customername,telephonenumber,addressid,t,id,t))
  cx_Oracle.DatabaseError: ORA-01722: invalid number
  </code></pre>