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https://issues.apache.org/jira/browse/SPARK-28389?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16885812#comment-16885812
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Dongjoon Hyun commented on SPARK-28389:
---------------------------------------
As a side note, this will be another instance which is different from Apache
Hive.
> Use Java 8 API to add months to dates
> -------------------------------------
>
> Key: SPARK-28389
> URL: https://issues.apache.org/jira/browse/SPARK-28389
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Affects Versions: 2.4.3
> Reporter: Maxim Gekk
> Assignee: Maxim Gekk
> Priority: Minor
> Fix For: 3.0.0
>
>
> The dateAddMonths() methods can be simplified by using the plusMonths()
> method of Java 8 LocalDate:
> {code}
> LocalDate.ofEpochDay(days).plusMonths(months)
> {code}
> This method adds the specified amount to the months field in three steps:
> # Add the input months to the month-of-year field
> # Check if the resulting date would be invalid
> # Adjust the day-of-month to the last valid day if necessary
> For example, 2019-01-31 plus one month would result in the invalid date
> 2019-02-31. Instead of returning an invalid result, the last valid day of the
> month, 2019-02-28, is selected instead.
> The valid result is returned as is. For example, adding 1 month to 2019-02-28
> is 2019-03-28.
> Mysql and PostgreSQL have the same behavior:
> {code}
> mysql> SELECT DATE_ADD("2019-01-31", INTERVAL 1 MONTH);
> +------------------------------------------+
> | DATE_ADD("2019-01-31", INTERVAL 1 MONTH) |
> +------------------------------------------+
> | 2019-02-28 |
> +------------------------------------------+
> 1 row in set (0.00 sec)
> mysql> SELECT DATE_ADD("2019-02-28", INTERVAL 1 MONTH);
> +------------------------------------------+
> | DATE_ADD("2019-02-28", INTERVAL 1 MONTH) |
> +------------------------------------------+
> | 2019-03-28 |
> +------------------------------------------+
> 1 row in set (0.00 sec)
> {code}
> {code}
> maxim=# SELECT DATE_ADD("2019-01-31", INTERVAL 1 MONTH);
> ERROR: syntax error at or near "1"
> LINE 1: SELECT DATE_ADD("2019-01-31", INTERVAL 1 MONTH);
> ^
> maxim=# SELECT DATE '2019-01-31' + INTERVAL '1 month';
> ?column?
> ---------------------
> 2019-02-28 00:00:00
> (1 row)
> maxim=# SELECT DATE '2019-02-28' + INTERVAL '1 month';
> ?column?
> ---------------------
> 2019-03-28 00:00:00
> (1 row)
> {code}
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