AdamGS opened a new pull request, #4389:
URL: https://github.com/apache/arrow-rs/pull/4389

   # Which issue does this PR close?
   
   <!--
   We generally require a GitHub issue to be filed for all bug fixes and 
enhancements and this helps us generate change logs for our releases. You can 
link an issue to this PR using the GitHub syntax. For example `Closes #123` 
indicates that this PR will close issue #123.
   -->
   
   Closes #4126 .
   
   # Rationale for this change
   For use cases that store large binary or string values in Parquet files, 
page-level statistics might blow up as the min/max values are stored in them as 
part of the [Column 
Index](https://github.com/apache/parquet-format/blob/master/PageIndex.md). This 
"feature" is part of the spec, and is implemented in other languages.
   <!--
   Why are you proposing this change? If this is already explained clearly in 
the issue then this section is not needed.
   Explaining clearly why changes are proposed helps reviewers understand your 
changes and offer better suggestions for fixes.
   -->
   
   # What changes are included in this PR?
   This adds a new member to `WriterProperties`, and truncates min/max values 
at a specific length, while still allowing shorter ones or disabeling 
truncation all together (maintaing the current default behavior).
   
   <!--
   There is no need to duplicate the description in the issue here but it is 
sometimes worth providing a summary of the individual changes in this PR.
   -->
   
   # Are there any user-facing changes?
   There are two user-facing changes in this PR:
   1. It adds a new option to `WriterPropertiesBuilder`to specify the max 
length of min/max values before they are truncated.
   2. It will change the default behavior to truncating at the 128 byte line. 
That might cause some performance changes to users that have long binary arrays 
with shared prefixes.
   
   <!---
   If there are any breaking changes to public APIs, please add the `breaking 
change` label.
   -->
   


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to