@Override
    public ClickHouseNestedValue copy(boolean deep) {
        if (!deep) {
            return new ClickHouseNestedValue(columns, getValue());
        }

        Object[][] value = getValue();
        int len = value.length;
        Object[][] newValue = new Object[len][];
        for (int i = 0; i < len; i++) {
            Object[] v = value[i];
            newValue[i] = Arrays.copyOf(v, v.length);
        }
        return new ClickHouseNestedValue(columns, newValue);
    }
Gets immutable list of nested columns.

@return immutable list of columns
clickhouse-data/src/main/java/com/clickhouse/data/value/ClickHouseNestedValue.java