updated alarms migration

Added foreign key and constraints for event+trigger time uniqueness

db/migrations/1624964657_create_alarms.h

@@ -10,11 +10,13 @@ namespace db {
         // action should be an enum
       m1624964657_create_alarms() : Migration() {
         db_builder::Table create_alarms = db_builder::Table::create("alarms"
-                                                          ).integer("id", "PRIMARY KEY"
-                                                          ).integer("eventID", "REFERENCES events(uid)"
+                                                          ).integer("id", "NOT NULL PRIMARY KEY"
                                                           ).text("description"
                                                           ).text("action"
                                                           ).text("absolute_trigger"
+                                                          ).integer("event_id", "NOT NULL"
+                                                          ).fk("event_id", "events", "id", "ON DELETE CASCADE ON UPDATE NO ACTION"
+                                                          ).constraint("event_time_unique", "event_id, absolute_trigger"
                                                           ).close();