debrouwere commented on issue #44725:
URL: https://github.com/apache/arrow/issues/44725#issuecomment-2538848374

   I wonder if you meant lazily evaluated, in the sense that, until `collect` 
is called, no data is read?
   
   With regards to tibbles and performance, my bad, I can see now that my 
comment was unclear. In R, I can take any tibble and then write that to disk as 
a hive-style Parquet dataset with `write_dataset`. Although writing to Parquet 
from a tibble doesn't produce any errors, I have noticed that if I then try to 
read the resulting dataset, it results in very slow reads and `invalid 
metadata$r` errors, which is what my original bug report was about. However, if 
instead I persist the dataset to disk using `my_tibble |> as.data.frame() |> 
write_dataset(...)` subsequent reads are much faster and don't result in 
`invalid metadata$r` errors. Therefore, my guess is that there is something 
suboptimal / weird about how data from tibbles is converted into Parquet. To be 
completely clear, I am talking about read performance, not about whether 
analysis with a data.frame or with a tibble is faster in R, which wouldn't 
really have anything to do with Parquet.


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