Обсуждение: Equivalent of Oracle next_day function

Is there a postgres equivalent of Oracle's next_day() function?  We have a web-based report that lists an employee's hours from Monday (of the current week) through the following Sunday (or sometimes the same period for the previous week); the beginning/end dates are retrieved (in Oracle) using the next_day function, ala:
        
        SELECT TO_CHAR ( ( NEXT_DAY ( SYSDATE, 'MONDAY' ) - 7 ), 'MM/DD/YY' ) AS THEMONDAY FROM DUAL

What would be the simplest way to do this query in PostgreSQL?

--

David Rickard
Software Engineer
The GTS Companies
A TechBooks Company

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I don't know of an equivalent but this should do what you want (this
gives you the preceding Sunday, add one to get Monday):

steve=# select current_date - date_part('dow', current_date)::int;

Make it a function if you like:

steve=# create function startofweek()
returns date
as
'select current_date - date_part(''dow'', current_date)::int+1'
language sql;

(note that's two single quotes not double quotes surrounding dow)

On Monday it will return the current Monday:

steve=#select startofweek();
 startofweek
-------------
 2003-10-13


Cheers,
Steve

On Monday 13 October 2003 4:28 pm, David Rickard wrote:
> Is there a postgres equivalent of Oracle's next_day() function?  We
> have a web-based report that lists an employee's hours from Monday
> (of the current week) through the following Sunday (or sometimes
> the same period for the previous week); the beginning/end dates are
> retrieved (in Oracle) using the next_day function, ala:
>
>          SELECT TO_CHAR ( ( NEXT_DAY ( SYSDATE, 'MONDAY' ) - 7 ),
> 'MM/DD/YY' ) AS THEMONDAY FROM DUAL
>
> What would be the simplest way to do this query in PostgreSQL?
>
>
>
> --
>
> David Rickard
> Software Engineer
> The GTS Companies
> A TechBooks Company
>
> -------------------------------------------------------------------
>---------------
>
> The GTS Companies:
> GTS Publishing Services, GTS Graphics, GTS Innova:
> Your Single-Source Solution!
> Los Angeles CA  *  York, PA  *  Boston MA  *  New Delhi, India
> -------------------------------------------------------------------
>---------------
>
>
>
> David.Rickard@GTSCompanies.com
> Visit us on the World Wide Web
> http://www.gtscompanies.com
> 5650 Jillson St., Los Angeles, CA 90040
> (323) 888-8889 x331
> (323) 888-1849 [fax]