[FIX] stock_account: stock valuation report performances

Basically, computation of the `inventory_value` is now done
in batch instead of one by one.

In a real use case, the computation of the stock valuation
passed from 20+ minutes to less than a minute.

This revision contains an unusual SQL request:
`SELECT DISTINCT ON`
Basically, it returns the most recent line of table
product_price_history for each tuple
`(product_template_id, company_id)`
which is actually what we want, with good performances.

See postgresql doc for more information:
http://www.postgresql.org/docs/9.0/static/sql-select.html#SQL-DISTINCT

opw-641154

0 files changed, 0 insertions, 0 deletions