Professional Web Applications Themes

averaging the datetime values - Informix

I want to average the datetime value in my query but it gives me the error saying average and sum cannot be used on datetime. Can someone please help me with this? Thanks...

  1. #1

    Default averaging the datetime values

    I want to average the datetime value in my query but it gives me the
    error saying average and sum cannot be used on datetime.
    Can someone please help me with this?

    Thanks
    SlowG Guest

  2. #2

    Default Re: averaging the datetime values

    SlowG wrote:
    > I want to average the datetime value in my query but it gives me the
    > error saying average and sum cannot be used on datetime.
    > Can someone please help me with this?

    Hmmm...

    You can add intervals, so you can probably average or sum them.
    I'm not sure what siginificance you could ever attach to the sum of a
    set of DATETIMES other than as a prelude to averaging them, anyway.

    So, you should probably simply decide to do something like:

    SELECT DATETIME(2000-01-01 00:00:00) YEAR TO SECOND +
    AVG(dtcolumn - DATETIME(2000-01-01 00:00:00) YEAR TO SECOND)

    When you do an AVG like this, the reference date (Y2K in the example)
    is immaterial as long as it is consistent. If you really, really want
    a SUM instead of an AVG, then you have to be careful about what you
    choose as a reference date -- though I would still question your
    understanding of the situation (or mine).

    --
    Jonathan Leffler #include <disclaimer.h>
    Email: [email]jlefflerearthlink.net[/email], [email]jlefflerus.ibm.com[/email]
    Guardian of DBD::Informix v2003.04 -- [url]http://dbi.perl.org/[/url]

    Jonathan Leffler Guest

  3. #3

    Default Re: averaging the datetime values

    Jonathan Leffler wrote:
    > SlowG wrote:
    >> I want to average the datetime value in my query but it gives me the
    >> error saying average and sum cannot be used on datetime.
    >> Can someone please help me with this?
    > You can add intervals, so you can probably average or sum them.
    > I'm not sure what siginificance you could ever attach to the sum of a
    > set of DATETIMES other than as a prelude to averaging them, anyway.
    >
    > So, you should probably simply decide to do something like:
    >
    > SELECT DATETIME(2000-01-01 00:00:00) YEAR TO SECOND +
    > AVG(dtcolumn - DATETIME(2000-01-01 00:00:00) YEAR TO SECOND)
    >
    > When you do an AVG like this, the reference date (Y2K in the example) is
    > immaterial as long as it is consistent. If you really, really want a
    > SUM instead of an AVG, then you have to be careful about what you choose
    > as a reference date -- though I would still question your understanding
    > of the situation (or mine).
    Urgh...you'd need to verify whether the difference between two
    DATETIME YEAR TO SECOND values is a sensibly-qualified INTERVAL DAY(N)
    TO SECOND value. If not, add INTERVAL(0 0:0:0) DAY(9) TO SECOND
    before the subtraction:

    AVG(INTERVAL(0 0:0:0) DAY(9) TO SECOND +
    (dtcolumn - DATETIME(2000-01-01 00:00:00) YEAR TO SECOND))

    --
    Jonathan Leffler #include <disclaimer.h>
    Email: [email]jlefflerearthlink.net[/email], [email]jlefflerus.ibm.com[/email]
    Guardian of DBD::Informix v2003.04 -- [url]http://dbi.perl.org/[/url]

    Jonathan Leffler Guest

Similar Threads

  1. Averaging data
    By Dave in forum PERL Modules
    Replies: 5
    Last Post: September 29th, 02:36 PM
  2. Why don?t the location values in the Sprite Overlay agree with the values
    By adiabatic webforumsuser@macromedia.com in forum Macromedia Director Basics
    Replies: 3
    Last Post: January 6th, 04:30 AM
  3. Replies: 1
    Last Post: December 6th, 01:55 AM
  4. Formatting datetime values
    By Vishal Parkar in forum Microsoft SQL / MS SQL Server
    Replies: 2
    Last Post: July 4th, 02:40 PM
  5. Adding custom values and database values to DropDwonList
    By William F. Robertson, Jr. in forum ASP.NET General
    Replies: 0
    Last Post: July 1st, 06:32 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139