@Override
    public String toString() {
        return "OperationStatistics{" +
                "\"queryId\"=\"" + queryId + "\", " +
                "\"metrics\"=" + metrics +
                '}';
    }
Complete counting metrics on operation and stop all stopwatches.
Multiple calls may have side effects.
Note: should not be called by user code, except when created by user code.
client-v2/src/main/java/com/clickhouse/client/api/metrics/OperationMetrics.java