Group operator OR

I have detected a bug when changing the variable "group_operator" using the function "set_group_operator" on "hook_views_query_alter" from "AND" to "OR"

the query remains with the value "AND"

I change the line number 1124 in the file "plugins / views_plugin_query_default.inc"
from "$main_group = db_and();"
to "$main_group = $this->group_operator == 'OR' ? db_or () : db_and ();"

and that work