HIVE-25292 : to_unix_timestamp & unix_timestamp should support ENGLIS…

[zzzzming95]

…H format by default

What changes were proposed in this pull request?

update to_unix_timestamp function, Now where the locale of the machine is not in English, the following sql can also return the result correctly:

select to_unix_timestamp('16/Mar/2017:12:25:01 +0800','dd/MMM/yyy:HH:mm:ss Z'); 

Why are the changes needed?

English date is a more common usage, if there is no such patch, in the local non-English environment, the following usage, to_unix_timestamp function will return NULL

hive> select to_unix_timestamp('16/Mar/2017:12:25:01','dd/MMM/yyy:HH:mm:ss');
OK
NULL

Does this PR introduce any user-facing change?

No

How was this patch tested?

To run hive in a non-English environment, the simpler way can use the jvm parameter

-Duser.country=cn -Duser.language=zh

Then run the following sql statement to test, if the timestamp is returned, it is correct.

[github-actions]

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[zzzzming95]

@kgyrtkirk Could you please review this fix ?

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.
Feel free to reach out on the dev@hive.apache.org list if the patch is in need of reviews.

[kgyrtkirk]

I think we could probably also consider also adding the US parsing instead of making it the default; what do you think?
so that it will work with the jvm's default locale and with US as well

[zzzzming95]

@kgyrtkirk

My initial thoughts were the same as you, but in this way you need to create two DateTimeFormatters, and it seems that you can only use try{} catch{} to control the code logic (or is there a better way ?), which is not very elegant.

Another reason is that I found in Apache Spark that spark to_unix_timestamp udf uses US Local to format the time by default.

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.
Feel free to reach out on the dev@hive.apache.org list if the patch is in need of reviews.