Enclose columns containing alphabets with single quotes using awk - unix

Question

Can awk process this?
Input
Neil,23,01-Jan-1990
25,Reena,19900203
Output
'Neil',23,'01-Jan-1990'
25,'Reena',19900203

Answer 1

awk approach:
awk -F, '{for(i=1;i<=NF;i++) if($i~/[[:alpha:]]/) $i="\047"$i"\047"}1' OFS="," file
The output:
'Neil',23,'01-Jan-1990'
25,'Reena',19900203
if($i~/[[:alpha:]]/) - if field contains alphabetic character
\047 - octal code of single quote ' character

Answer 2

Incorrect was my first attempt
sed -r 's/([^,]*[a-zA-Z]+[^,]*)(,{0,1})/"\1"\2/g' inputfile
#Sundeep gave an excellent comment: I need single quotes and it can be shorter:
I tried to match including the , of end-of-line, causing some complexity for matching. You can just match between the seperators making sure there is an alphabetic character somewhere.
sed 's/[^,]*[a-zA-Z][^,]*/\x27&\x27/g' inputfile

Answer 3

You might use this script:
script.awk
BEGIN { OFS=FS="," }
{ for(i= 1; i<=NF; i++) {
if( !match( $i, /^[0-9]+$/ ) ) $i = "'" $i "'"
}
print
}
and run it like this: awk -f script.awk yourfile .
Explanation
the first line sets up the input and output Fieldseparators to ,.
the loop tests each field, whether it contains only digits (/^[0-9]+$/):
if not the field is put in quotes