Shell Programming and Scripting

cat file1.csv

ID	city	acct_no
1	blr	500
1	chn	600
1	dlh	700
2	hyd	888
2	blr	999
3	dlh	111
3	blr	222
3	hyd	333


Required output

ID	city	acct_no
1	blr|chn|dlh	500|600|700
2	hyd|blr	888|999
3	blr|hyd	111|222|333

3	dlh|blr|hyd	111|222|333

3	blr|hyd	111|222|333

awk '
BEGIN { OFS="\t" }
$1 != last_id {
        if(NR > 1) print last_id, cities, accounts
        last_id = $1
        cities = $2
        accounts = $3
        next
}
{       cities = cities "|" $2
        accounts = accounts "|" $3
}
END {   print last_id, cities, accounts }' file1.csv

awk '
 NR==1{
  h=$0
 } 
 NR>1{
  c[$1]=c[$1]?c[$1]"|"$2:$2
  a[$1]=a[$1]?a[$1]"|"$3:$3
 } 
 END{
  print h
  for (i in c) print i,c[i],a[i]
 }' file

awk '
 NR==1{
  print
  next
 }
 {
  for (i=2; i<=NF; i++) {
   a[$1,i]=a[$1,i]?a[$1,i]"|"$i:$i
  }
  l[$1]
 }
 END {
  for (i in l) {
   printf("%s ", i)
   for (j=2; j<=NF; j++) {
    printf("%s ",a[i,j])
   }
   printf "\n"
  }
 }' file