Re: Fetching last n records from Posgresql

Il 30/03/2016 11:36, Deole, Pushkar
      (Pushkar) ha scritto:

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        <span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I
            am sorry I didn’t clarify my requirement properly.. I want
            the ‘n’ oldest records, however, they should sorted with the
            recent record first and I want this to happen in the query
            itself so I don’t have to care about sorting through the
            application..
        <span
style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> 

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            <span
style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext">From:<span
style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext">
                pgsql-general-owner@postgresql.org
                [mailto:pgsql-general-owner@postgresql.org]
                On Behalf Of Moreno Andreo
                Sent: Wednesday, March 30, 2016 3:03 PM
                To: pgsql-general@postgresql.org
                Subject: Re: [GENERAL] Fetching last n records
                from Posgresql


         

          Il 30/03/2016 11:19, Deole, Pushkar
            (Pushkar) ha scritto:


          select * from t order by record_date desc
            limit 5;
           
          this will return the recent 5 records..
            what I want is the oldest 5 records (in last 30 days)

        so remove
          "desc", in order to have ascending ordering, thus first 5
          records are the five oldest:

          select * from t order by record_date limit 5

          Cheers
          Moreno.-




    select * from (select * from t where record_date >=current_date()
    - '30 days' order by record_date limit 5) order by record_date desc

    Not tested, but should work...

    Cheers
    Moreno.-