@Override
    public DPColumn column(int colId) {
        if (update) {
            return null;
        }
        return super.column(colId);
    }
Open a DPSegment.

The newly open segment cannot be updated.
You can use {@link #update()} to enable update.

@param version The segment version, check {@link Version}.
@param mode    The segment mode.
@param path    The path of segment.
@param name    The unique segment identifier in the whole system.
@param schema  The schema of segment.
@param options The open options.
@return A segment resides on the path.
indexr-segment/src/main/java/io/indexr/segment/storage/DPSegment.java