[GitHub] [arrow] mapleFU commented on issue #14923: [C++][Parquet] DeltaBitPackDecoder expects all miniblock bitwidths to be present for the last block

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mapleFU commented on issue #14923:
URL: https://github.com/apache/arrow/issues/14923#issuecomment-1366657071

   @rok I reproduce this problem on my pc by applying the change below:
   
   ```diff
   -  for (uint32_t i = num_miniblocks; i < mini_blocks_per_block_; i++) {
   -    bit_width_data[i] = 0;
   -  }
   +  // for (uint32_t i = num_miniblocks; i < mini_blocks_per_block_; i++) {
   +  //  bit_width_data[i] = 0;
   +  // }
   ```
   
   But I think the code just break our standard, by unuse `bit_width_data[i] = 
0;`, we will leak some mini-blocks, the real code would be:
   
   ```c++
    for (uint32_t i = num_miniblocks; i < mini_blocks_per_block_; i++) {
       bit_width_data[i] = 1 /* or other random bit width for miniblock */;
       for (uint32_t j = 0; j < values_per_mini_block_; j++) {
          bit_writer_.PutValue(0, bit_width_data[i]);
       }
    }
   ```
   
   And previous case would lead to:
   * write less bits than expected for the last block
   * Last block `bit_width_data` random
   
   So I think here is no bug. If I'm wrong, please correct me @rok 


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