public void pointTo(byte[] buf, int sizeInBytes) {
        pointTo(buf, Platform.BYTE_ARRAY_OFFSET, sizeInBytes);
    }
Update this UnsafeRow to point to the underlying byte array.

@param buf         byte array to point to
@param sizeInBytes the number of bytes valid in the byte array
indexr-query-opt/src/main/java/io/indexr/query/row/UnsafeRow.java