[PERF] mrp,stock,purchase: sql improvement

First correction: replace call to `read_group` to `_read_group` in order
to avoid useless joints on table product_template and ir_translation
when the grouping key is a Many2One.

Second correction: add an index on workorder's `state` field. The
get_conflicted_workorder_ids() method search for ready workorders that
are in conflict relate to their planning. The state value is searched to
many times to not index it

closes odoo/odoo#106582

Task: 2852423
X-original-commit: b5019eec76845316e554f2dd11a6d8bbf6fea433
Signed-off-by: Arnold Moyaux (arm) <arm@odoo.com>
Signed-off-by: William Henrotin (whe) <whe@odoo.com>

addons/mrp/models/mrp_workorder.py

@@ -63,7 +63,7 @@ class MrpWorkorder(models.Model):
         ('done', 'Finished'),
         ('cancel', 'Cancelled')], string='Status',
         compute='_compute_state', store=True,
-        default='pending', copy=False, readonly=True, recursive=True)
+        default='pending', copy=False, readonly=True, recursive=True, index=True)
     leave_id = fields.Many2one(
         'resource.calendar.leaves',
         help='Slot into workcenter calendar once planned',

addons/purchase_stock/models/product.py

@@ -33,7 +33,7 @@ class ProductProduct(models.Model):
 
         qty_by_product_location, qty_by_product_wh = super()._get_quantity_in_progress(location_ids, warehouse_ids)
         domain = self._get_lines_domain(location_ids, warehouse_ids)
-        groups = self.env['purchase.order.line'].read_group(domain,
+        groups = self.env['purchase.order.line']._read_group(domain,
             ['product_id', 'product_qty', 'order_id', 'product_uom', 'orderpoint_id'],
             ['order_id', 'product_id', 'product_uom', 'orderpoint_id'], lazy=False)
         for group in groups: