problem about gql-Collection of common programming errors

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  c4sh
  javascript python html google-app-engine gql
  what I’m trying to do is have a upload button to upload files to our storage system. I’m using Google App Engine with Python. Also HTML and Javascript for views.For that, we have a HTML, and a.js that asks the user if he’s sure that he wants to overwrite a file. For that overwriting question, I need to ask the Database to know if it exists,and so if the question should be asked or not…The thing is I don’t know even where to start. I have this confirm() text shown to the user, and a GQL database, but I don’t know how to make a question. For example, I upload via a URL, but then I don’t have a response for that, and also I don’t want to pass a question (name of the file,…) to the database via URL…Do you have any idea of what path should I follow? Am I trying something impossible or without any sense?Thanks a lot!I add some code:this is the HTML form where we ask the user to upload a file:

Originally posted 2013-11-06 03:12:51.