Comment 12 for bug 1155606

Hello,

I am sorry for previous copy-paste comment.

tax_amount is fine example of data duplication.
As always, data duplication anomalies leads to strange "cure the symptoms" solutions like:
 - read only, hidden, calculated,
 - hidden,trigger
 - divergent constraints in Vauxoo and other localization modules

Solution I propose :
This field must be depreciated.
Accounting practice have to be improved.
Tax reports based on credit/debit (+tax code properties for sign).

But, before all that, posting of taxes needs improvement.
Specifically:
  Partly/fully nondeductible taxes (Vat and/or Profit tax):
     Extracted from Croatian localization. Far from Community modules standards yet!
      http://bazaar.launchpad.net/~gkliska/addons-sp/slobodni_addons_61/files/head:/account_tax_nondeductable/
     Italian localization
  Vat deductible on Payment:
      Again mix of Italian and Cratian localization as reference
      http://bazaar.launchpad.net/~gkliska/addons-sp/slobodni_addons_61/files/head:/account_tax_payment/
  VAT on Import
      There was video on c2c web explaining the technique.
  Invoice with 0.0€ or Gifts
      Here, (by law) we have to post +-market value and pay the VAT on it.
      AFAIK it is certainly not bad practice to book in 2 lines (100€ market value, 25% VAT):

Thanks,
PS Just say NO to data duplications in OpenERP! :)