in grafana/alert/condition.js [68:77]
function onQuery(query, duration, from) {
if (typeof query !== 'string') {
throw Error('Query identifier must be a string. eg. "A" or "B", etc...');
}
that._query.params[0] = query;
that._query.params[1] = duration;
that._query.params[2] = from;
return this;
}