[Trunk] Group By function field should be display aggregate instead of sum.

[wowas]

It is very difficult made GROUP BY in TREE VIEW or in GRAPH VIEW, if field calculate from other fields.
For example we have table with following fields:
date (Date of production)
prod_qty (Total Quantity produced items)
reject_qty (Quantity of rejected items)
quality (Calculated field: quality = reject_qty/prod_qty)

If we try GROUP BY 'date' then for some date we get:

PROD_QTY = SUM(prod_qty of the same date)
REJECT_QTY = SUM(reject_qty of the same date)
QUALITY = SUM(quality of the same date)

But for agregate QUALITY = REJECT_QTY/PROD_QTY = SUM(reject_qty of the same date)/SUM(prod_qty of the same date)
Because it no the same as SUM(quality of the same date), need add extra code (for example rewrite function read_group())

It will be more cool if we have functional attribute for field, that will describe custom agregate function other than SUM().

[Jignesh Rathod(OpenERP) (jir-openerp)]

Hello wowas ,

Sorry for Inconvenience , But It's not totally duplicate of the bug : 1001659
and I agree with you It should be display a aggregate rather then sum.
So I am Confirming this issue for Framework.

Thank you!