Frequently Asked Questions (FAQ)

Frequently Encountered Problems

If it happens that you notice the following in the Traceback of the ticket encountered after a fresh pull -
OperationalError: Cannot add a UNIQUE column

Then it is highly likely that there is a data migration issue. In this circumstance, it is recommended that the contents of the folder /eden/database/ be deleted. For more, information in this regard and any other related problem, the following links can be referred from -

Select Element for Users

By: Robby O'Connor
Date: 2010-05-21

To have a field displayed as a select element which has the names of the users in the database:

<table>.<field>.requires = IS_NULL_OR(IS_IN_DB(db,,lambda id : shn_user_represent(

Interactive vs. Non-Interactive Functions

  • Interactive = via web browser (html)
  • Non-Interactive = Sync, import, etc (xml, csv)

Never do a redirect or create records (the latter is slightly less 100%) in non-interactive functions.

All resources should assume to be touched non-interactively at some point (even if just to load test/demo data)

onaccept & onvalidation are always called by non-interactive functions

Protect sections within these functions to be only accessed via interactive calls using:

if isinstance(form, FORM):
    # Interactive request

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Last modified 5 years ago Last modified on 04/18/19 13:58:42
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