[GitHub] [arrow] phpsxg commented on issue #14725: How to partition by quantity with write_to_dataset

[GitBox <gi...@apache.org>]

phpsxg commented on issue #14725:
URL: https://github.com/apache/arrow/issues/14725#issuecomment-1327188431

   > Without knowing what your data looks like it is hard to say how to better partition it. But you can raise the maximum number of partitions via `max_partitions` which defaults to 1024 or you could just limit the number of rows per file if you don't have a more specific partitioning scheme with `max_rows_per_file`: https://arrow.apache.org/docs/python/generated/pyarrow.dataset.write_dataset.html#pyarrow.dataset.write_dataset
   > 
   > Feel free to close the issue if this answers your question.
   
   
   Thank you, ds.write_dataset meets my needs, but I have two more questions
   
   1. Is there any difference between **pq.write_to_dataset** and **ds.write_dataset**?
   2. How to implement dynamic filtering with ds.write_dataset, if the filters I get according to different parameters are a list
   
   For example, there are two filters, which is fine
   `df = dataset.to_table(filter=( ds.field('c').is_null()) & (ds.field('b') > 0)).to_pandas()`
   
   But if the filter is a list, how to pass the parameters
   ```
   filters = []
   if ...:
       filters.append(ds.field('c').is_null())
   if ....:
       filters.append(ds.field('b') > 0)
   ```


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