IDS Forum

Re: AWK question

Posted By: Art Kagel
Date: Wednesday, 12 October 2011, at 10:42 a.m.

In Response To: Re: AWK question (Walt Hultgren)

Good point Walt. The worst that I've seen are the awk's on Solaris and AIX
which also have some old bugs like not properly supporting input variables
(-v varname=value). On Solaris you usually also have nawk which works fine
and some installations of Solaris have GNU awk (gawk) which is available for
AIX as well. Nawk and gawk have many extensions to the basic awk language
as well.

Art

Art S. Kagel
Advanced DataTools (www.advancedatatools.com)
Blog: http://informix-myview.blogspot.com/

Disclaimer: Please keep in mind that my own opinions are my own opinions and
do not reflect on my employer, Advanced DataTools, the IIUG, nor any other
organization with which I am associated either explicitly, implicitly, or by
inference. Neither do those opinions reflect those of other individuals
affiliated with any entity with which I am affiliated nor those of the
entities themselves.

On Wed, Oct 12, 2011 at 10:08 AM, Walt Hultgren <walt@altasenta.com> wrote:

> On Oct 12, 2011, at 8:10 AM, Dirk Cornel.... wrote:
>
> > Great, thank you. I knew some very basic one liners in awk, but awk is a
> whole
> > language in itself. Very cool. Did my 1st multiple line script yesterday.
> >
> > Dirk
>
> Congratulations! You are now an official "developer" (if you weren't one
> already). :-)
>
> One more point about awk: I'm not familiar with all of the various
> implementations of awk, but at least the older ones tended to have what we
> would now consider fairly low limitations on the maximum allowed length of
> any
> one input record. Those limits would not be dynamically resized, either.
> You
> got what you got. This may not apply to the awk in in your environment
> (awk,
> nawk, gawk, ...), but it's something to be aware of.
>
> I don't recall seeing what your overall application is. If what you're
> planning will be mission critical and/or subject to very long input
> records, I
> suggest you try some stress testing with what you consider a worst case set
> of
> input.
>
> HTH,
>
> Walt.
>
> >
> >> -----Original Message-----
> >> From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] On Behalf Of
> >> Art Kagel
> >> Sent: Wednesday, 12 October 2011 01:19 PM
> >> To: ids@iiug.org
> >> Subject: Re: AWK question [25177]
> >>
> >> Yes. Or just combine the functionality into one script. Any text that
> >> passes one braced section falls through to the next one unless the
> >> section
> >> ends with a 'next;' statement. So:
> >>
> >> cat file | awk ' {some stuff}' | awk '{other stuff}'
> >>
> >> is equivalent to:
> >>
> >> cat file | awk '{some stuff'} {other stuff}'
> >>
> >> with less overhead because only one copy of awk is running.
> >>
> >> Art
> >>
> >> Art S. Kagel
> >> Advanced DataTools (www.advancedatatools.com)
> >> Blog: http://informix-myview.blogspot.com/
> >>
> >> Disclaimer: Please keep in mind that my own opinions are my own
> >> opinions and
> >> do not reflect on my employer, Advanced DataTools, the IIUG, nor any
> >> other
> >> organization with which I am associated either explicitly, implicitly,
> >> or by
> >> inference. Neither do those opinions reflect those of other individuals
> >> affiliated with any entity with which I am affiliated nor those of the
> >> entities themselves.
> >>
> >> On Wed, Oct 12, 2011 at 5:01 AM, Dirk Cornel....
> >> <moolma_dc@mtn.co.za>wrote:
> >>
> >>> Last question ... PS. I love Unix :-)
> >>>
> >>> I assume if I have multiple awk "functions" like the one below, I can
> >> pipe
> >>> one
> >>> awk to the next ?
> >>>
> >>> Eg.
> >>>
> >>> Awk ' ..... do my stuff ..... '
> >>>
> >>> |
> >>>
> >>> Awk ' ..... do some more stuff ..... '
> >>>
> >>>> -----Original Message-----
> >>>> From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] On Behalf
> >> Of
> >>>> Art Kagel
> >>>> Sent: Tuesday, 11 October 2011 06:58 PM
> >>>> To: ids@iiug.org
> >>>> Subject: Re: AWK question [25167]
> >>>>
> >>>> Something like this:
> >>>>
> >>>> awk '
> >>>> BEGIN {idx=0;}
> >>>> {
> >>>>
> >>>> if (name[$1] == $1) {
> >>>>
> >>>> count[$1] += 1;
> >>>>
> >>>> } else {
> >>>>
> >>>> name[$1] = $1;
> >>>>
> >>>> count[$1] = 1;
> >>>>
> >>>> }
> >>>> }
> >>>> END {
> >>>>
> >>>> for (aname in name) {
> >>>>
> >>>> print aname, count[aname];
> >>>>
> >>>> }
> >>>> }' filepath
> >>>>
> >>>> Art
> >>>>
> >>>> Art S. Kagel
> >>>> Advanced DataTools (www.advancedatatools.com)
> >>>> Blog: http://informix-myview.blogspot.com/
> >>>>
> >>>> Disclaimer: Please keep in mind that my own opinions are my own
> >>>> opinions and
> >>>> do not reflect on my employer, Advanced DataTools, the IIUG, nor
> >> any
> >>>> other
> >>>> organization with which I am associated either explicitly,
> >> implicitly,
> >>>> or by
> >>>> inference. Neither do those opinions reflect those of other
> >> individuals
> >>>> affiliated with any entity with which I am affiliated nor those of
> >> the
> >>>> entities themselves.
> >>>>
> >>>> On Tue, Oct 11, 2011 at 12:44 PM, Dirk Cornel....
> >>>> <moolma_dc@mtn.co.za>wrote:
> >>>>
> >>>>> If I have a text file in Unix, how can I do the following on the
> >> text
> >>>> file
> >>>>> using awk ?
> >>>>>
> >>>>> select column1, count(*)
> >>>>> from tablename
> >>>>> group by 1
> >>>>>
> >>>>> Sorry, I did not know how else to ask the question, but I am
> >> trying
> >>>> to do
> >>>>> this
> >>>>> on a text file, without having to load the file into Informix,
> >>>> running the
> >>>>> select and then unloading the result again.
> >>>>> Ie. I want to do this straight in Unix without using Informix. My
> >>>> knowledge
> >>>>> of
> >>>>> awk is very basic, ie:
> >>>>>
> >>>>> Cat filename | awk '{print $1}' ..... print column 1
> >>>>>
> >>>>> Cat filename | awk 's+=$1{print s}' ...... sum of column 1
> >>>>>
> >>>>> but I do not know how to do a count, group by in awk.
> >>>>>
> >>>>> NOTE: This e-mail message is subject to the MTN Group disclaimer
> >> see
> >>>>> http://www.mtn.co.za/SUPPORT/LEGAL/Pages/EmailDisclaimer.aspx
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>
> >> ***********************************************************************
> >>>> ********
> >>>>> Forum Note: Use "Reply" to post a response in the discussion
> >> forum.
> >>>>>
> >>>>>
> >>>>
> >>>> --90e6ba6e827a3d918704af08cf7e
> >>>>
> >>>>
> >>>>
> >> ***********************************************************************
> >>>> ********
> >>>> Forum Note: Use "Reply" to post a response in the discussion forum.
> >>>
> >>> NOTE: This e-mail message is subject to the MTN Group disclaimer see
> >>> http://www.mtn.co.za/SUPPORT/LEGAL/Pages/EmailDisclaimer.aspx
> >>>
> >>>
> >>>
> >>>
> >> ***********************************************************************
> >> ********
> >>> Forum Note: Use "Reply" to post a response in the discussion forum.
> >>>
> >>>
> >>
> >> --90e6ba21219b49245304af182e4f
> >>
> >>
> >> ***********************************************************************
> >> ********
> >> Forum Note: Use "Reply" to post a response in the discussion forum.
> >
> > NOTE: This e-mail message is subject to the MTN Group disclaimer see
> > http://www.mtn.co.za/SUPPORT/LEGAL/Pages/EmailDisclaimer.aspx
> >
> >
> >
>
> *******************************************************************************
> > Forum Note: Use "Reply" to post a response in the discussion forum.
> >
>
> --
> Walt Hultgren
> walt@altasenta.com
>
>
>
> *******************************************************************************
> Forum Note: Use "Reply" to post a response in the discussion forum.
>
>

--20cf303bfbde885d5104af1b07d2

Messages In This Thread

• AWK question
  Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Tuesday, 11 October 2011, at 12:44 p.m.
  • Re: AWK question
    Jack Parker -- Tuesday, 11 October 2011, at 12:51 p.m.
    • Re: AWK question
      Jack Parker -- Tuesday, 11 October 2011, at 1:00 p.m.
  • Re: AWK question
    Art Kagel -- Tuesday, 11 October 2011, at 12:58 p.m.
    • RE: AWK question
      Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Wednesday, 12 October 2011, at 5:01 a.m.
      • Re: AWK question
        Jack Parker -- Wednesday, 12 October 2011, at 7:18 a.m.
      • Re: AWK question
        Art Kagel -- Wednesday, 12 October 2011, at 7:18 a.m.
        • RE: AWK question
          Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Wednesday, 12 October 2011, at 8:10 a.m.
          • Re: AWK question
            Walt Hultgren -- Wednesday, 12 October 2011, at 10:08 a.m.
            • Re: AWK question
              Art Kagel -- Wednesday, 12 October 2011, at 10:42 a.m.
              • Re: AWK question
                Jack Parker -- Wednesday, 12 October 2011, at 11:01 a.m.
            • RE: AWK question
              Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Friday, 14 October 2011, at 5:29 a.m.
  • Re: AWK question
    John Miller iii -- Tuesday, 11 October 2011, at 1:11 p.m.
    • Re: AWK question
      Walt Hultgren -- Tuesday, 11 October 2011, at 2:19 p.m.
      • RE: AWK question
        Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Wednesday, 12 October 2011, at 4:44 a.m.

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