BryanCutler opened a new pull request #26496: [WIP][SPARK-29748][PYTHON][SQL] 
Remove Row field sorting in PySpark
URL: https://github.com/apache/spark/pull/26496
 
 
   <!--
   Thanks for sending a pull request!  Here are some tips for you:
     1. If this is your first time, please read our contributor guidelines: 
https://spark.apache.org/contributing.html
     2. Ensure you have added or run the appropriate tests for your PR: 
https://spark.apache.org/developer-tools.html
     3. If the PR is unfinished, add '[WIP]' in your PR title, e.g., 
'[WIP][SPARK-XXXX] Your PR title ...'.
     4. Be sure to keep the PR description updated to reflect all changes.
     5. Please write your PR title to summarize what this PR proposes.
     6. If possible, provide a concise example to reproduce the issue for a 
faster review.
   -->
   
   ### What changes were proposed in this pull request?
   <!--
   Please clarify what changes you are proposing. The purpose of this section 
is to outline the changes and how this PR fixes the issue. 
   If possible, please consider writing useful notes for better and faster 
reviews in your PR. See the examples below.
     1. If you refactor some codes with changing classes, showing the class 
hierarchy will help reviewers.
     2. If you fix some SQL features, you can provide some references of other 
DBMSes.
     3. If there is design documentation, please add the link.
     4. If there is a discussion in the mailing list, please add the link.
   -->
   Removing the sorting of PySpark SQL Row fields that were previously sorted 
by name alphabetically. Rows are now used like tuples and are applied to 
schemas by position.
   
   
   ### Why are the changes needed?
   <!--
   Please clarify why the changes are needed. For instance,
     1. If you propose a new API, clarify the use case for a new API.
     2. If you fix a bug, you can clarify why it is a bug.
   -->
   This caused inconsistent behavior in that local Rows could be applied to a 
schema by matching names, but once serialized the Row could only be used by 
position and the fields were possibly in a different order.
   
   ### Does this PR introduce any user-facing change?
   <!--
   If yes, please clarify the previous behavior and the change this PR proposes 
- provide the console output, description and/or an example to show the 
behavior difference if possible.
   If no, write 'No'.
   -->
   Yes, Row fields are no longer sorted alphabetically. For Python < 3.6 
`kwargs` can not guarantee the order as entered, so `Row`s can no longer be 
created with `kwargs`. Instead users can pass in a `collections.OrderedDict` or 
construct `Row`s in other ways.
   
   An environment variable "PYSPARK_LEGACY_ROW_ENABLED" can be set that will 
override construction of `Row` to maintain compatibility with Spark 2.x. 
   
   
   ### How was this patch tested?
   <!--
   If tests were added, say they were added here. Please make sure to add some 
test cases that check the changes thoroughly including negative and positive 
cases if possible.
   If it was tested in a way different from regular unit tests, please clarify 
how you tested step by step, ideally copy and paste-able, so that other 
reviewers can test and check, and descendants can verify in the future.
   If tests were not added, please describe why they were not added and/or why 
it was difficult to add.
   -->
   Modified existing tests for new behavior and added new tests for `LegacyRow`
   

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


With regards,
Apache Git Services

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to