diff --git a/runbot/models/build.py b/runbot/models/build.py
index aa2dd566..847e7821 100644
--- a/runbot/models/build.py
+++ b/runbot/models/build.py
@@ -51,7 +51,7 @@ class runbot_build(models.Model):
     # state machine
 
     global_state = fields.Selection(make_selection(state_order), string='Status', compute='_compute_global_state', store=True)
-    local_state = fields.Selection(make_selection(state_order), string='Build Status', default='pending', required=True, oldname='state')
+    local_state = fields.Selection(make_selection(state_order), string='Build Status', default='pending', required=True, oldname='state', index=True)
     global_result = fields.Selection(make_selection(result_order), string='Result', compute='_compute_global_result', store=True)
     local_result = fields.Selection(make_selection(result_order), string='Build Result', oldname='result')
     triggered_result = fields.Selection(make_selection(result_order), string='Triggered Result')  # triggered by db only