CODEWITHSUNDEEP
linuxbashawk
123onetwothree
123onetwothree

Reputation: 686

Bash modify CSV to change a field

I have a very big CSV file (aprox. 10.000 rows and 400 columns) and I need to modify certain columns (like 15, 156, 220) to change format from 20140321132233 to 2014-03-21 13:22:33. All fields that I need to modify are datetime.

I saw some examples using awk but for math modifications. Can I use something like this for doing the above change?

file.csv example:

19238328932|123233443|123|0|||||123123|20140321132233|1|0|0|....|20130211122143|...
12332312211|222321233|111|0|||||234432|20150222122354|1|0|0|....|20120112123133|...

Upvotes: 2

Views: 436

Answers (1)

NarūnasK
NarūnasK

Reputation: 4950

Please save following awk script as awk.src:

function date_str(val) {
  Y = substr(val,0,4);
  M = substr(val,5,2);
  D = substr(val,7,2);
  date = sprintf("%s-%s-%s",Y,M,D);
  return date;
}
function time_str(val) {
  h = substr(val,9,2);
  m = substr(val,11,2);
  s = substr(val,13,2);
  time = sprintf("%s:%s:%s",h,m,s);
  return time;
}

BEGIN {
  FS="|"
}
#
## MAIN Block
#
{
  for (i=1;i<=NF;i++) {
    if (i==10) {
      printf "%s %s", date_str($i), time_str($i);
    }
    else { printf $i; }
    if (i!=NF) {
      printf FS;
    }
    else { printf "\n"; }
  }
}

Now try it, it should print:

$ awk -f awk.src csv 
19238328932|123233443|123|0|||||123123|2014-03-21 13:22:33|1|0|0|....|20130211122143|...
12332312211|222321233|111|0|||||234432|2015-02-22 12:23:54|1|0|0|....|20120112123133|...

Upvotes: 4

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