Thanks, Wes. Does the metadata had through pq.ParquetFile(path).metadata (or 
.schema) include user metadata? I only see num rows, num row groups, column 
names and types. Maybe I'm not looking in the right place.

-Mike

-----Original Message-----
From: Wes McKinney [mailto:[email protected]] 
Sent: Tuesday, July 25, 2017 21:54
To: [email protected]
Subject: Re: metadata reading

hi Mike,

You can use

import pyarrow.parquet as pq
pf = pq.ParquetFile(path)
pf.metadata

or

pf.schema

This does not read the whole file, only the metadata. Note that we have a 
function write_metadata:

https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_apache_arrow_blob_master_python_pyarrow_parquet.py-23L777&d=DwIFaQ&c=f5Q7ov8zryUUIGT55zpGgw&r=p7uiAfJkXEwbVhZPqB-VxtsgxuGNpO5tGgnMUX3wqrPAIvdxhcKmn9kvZiXDziBQ&m=p8TXns9StzX8qUpC8khlvaVMtnIEoYBx3x7KepiHPik&s=CDhC_IzUBRYUYiD7HcDAz8uifHz4vjusDbw5Uejgeko&e=
 

It would be nice to have a pq.read_metadata method also. I opened a JIRA 
https://urldefense.proofpoint.com/v2/url?u=https-3A__issues.apache.org_jira_browse_ARROW-2D1273&d=DwIFaQ&c=f5Q7ov8zryUUIGT55zpGgw&r=p7uiAfJkXEwbVhZPqB-VxtsgxuGNpO5tGgnMUX3wqrPAIvdxhcKmn9kvZiXDziBQ&m=p8TXns9StzX8qUpC8khlvaVMtnIEoYBx3x7KepiHPik&s=FUF76j72E5P8GVKAHyGDCniNK6Jmnd8y6HFxUgxAi1I&e=
  since this will lead to a patch in Arrow.

- Wes

On Tue, Jul 25, 2017 at 3:54 PM, Katelman, Michael 
<[email protected]> wrote:
> Hi,
>
> I was wondering if someone could help me with a metadata-related 
> question. Is there anything exposed in pyarrow that would allow me to 
> read parquet metadata without reading the entire file? Currently, I 
> use
>
> pyarrow.parquet.read_table(path).schema.metadata
>
> to get the metadata, but would like to be able to get at it without reading 
> the entire table.
>
> -Mike
>
>
>
>
>
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