Unix Parsing and grouping with AWK

[Josef_Stalin]

When parsing multiple fields in a csv file using AWK, how do you group by one of the fields and

parse by delimiters?

[Josef_Stalin]

to clarify

If a file had
tom, 223-2222-4444, randomfield
ivan, 123-2422-4444, random filed

How would you group by the social security while parsing the (comma delimited) fields using awk?

[BioPhysEngr]

I'm not sure what you mean by parse by delimiters, but if you wanted to sort this file by the SSN-like fields, you could do this with:

cat test.txt | sort -k2 -t ,

Actually, I would want to get rid of the spaces after the commas too so I would use:

cat test.txt | sed 's/, /,/g' | sort -k2 -t ,

I very rarely use awk. Almost always I use grep, sed and sort for simple things on command line. They are extremely powerful when piped together. Anything more complicated and perl is usually a faster choice (for me anyway, YMMV).