Select only id from query of ModelSQL.search

Closes #13421
(grafted from c544661300ba3dc53db4378d4070b4aae8c5c32e)

--HG--
branch : 7.0

trytond/trytond/model/modelsql.py

@@ -1783,12 +1783,15 @@ class ModelSQL(ModelStorage):
         order_by = cls.__search_order(order, tables)
         # compute it here because __search_order might modify tables
         table = convert_from(None, tables)
-        columns = cls.__searched_columns(main_table, eager=not query)
-        if backend.name == 'sqlite':
-            for column in columns:
-                field = cls._fields.get(column.output_name)
-                if field:
-                    column.output_name += ' [%s]' % field.sql_type().base
+        if query:
+            columns = [main_table.id.as_('id')]
+        else:
+            columns = cls.__searched_columns(main_table, eager=True)
+            if backend.name == 'sqlite':
+                for column in columns:
+                    field = cls._fields.get(column.output_name)
+                    if field:
+                        column.output_name += ' [%s]' % field.sql_type().base
         select = table.select(
             *columns, where=expression, limit=limit, offset=offset,
             order_by=order_by)