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https://issues.apache.org/jira/browse/CALCITE-759?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16810016#comment-16810016
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Julian Hyde commented on CALCITE-759:
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[~Stabmeqt] See the discussion in IMPALA-4018 about how Hive and Impala used
SimpleDateFormat and how it was a mistake.
For example, they give this example:
{noformat}
-- PostgreSQL/Netezza/Vertica/Oracle
select to_timestamp('May 15, 2015 12:00:00', 'mon dd, yyyy hh:mi:ss');
-- Impala
select to_timestamp('May 15, 2015 12:00:00', 'MMM dd, yyyy HH:mm:ss');
{noformat}
We must be compatible with PostgreSQL/Netezza/Vertica/Oracle
> Add DayOfWeek and other missing date/time functions
> ---------------------------------------------------
>
> Key: CALCITE-759
> URL: https://issues.apache.org/jira/browse/CALCITE-759
> Project: Calcite
> Issue Type: Bug
> Components: babel
> Reporter: Julian Hyde
> Priority: Major
> Labels: dialect, newbie
>
> Calcite implements EXTRACT, FLOOR, CEIL, CAST, +, - on date/time values and
> much can be accomplished with these. But there are other useful functions in
> other databases.
> For example MySQL has DayOfWeek. See
> https://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html. It is
> tricky to achieve the same in Calcite (you'd need to subtract the epoch and
> take the interval modulo 7).
> We need to review the date/time functions in MySQL, Postgres and Oracle, and
> add functions to ensure that you can accomplish the same things in Calcite
> fairly easily.
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