SERIES : awk#3 Match only a specific field

Here's the input file with employee data.

$cat empf
100,Smith James,80000,101 Ave N,San Francisco,CA
200,Lloyd Beth,80000,2010 University St,San Francisco,CA
300,Doe John,90000,1005 Royal Dr,Hartford,CT
400,Day Matt,85000,100 W 4th Ave,Seattle,WA
700,Bell Amy,60000,201 Winner CT,Atlanta,GA
800,Hawn Ruby,75000,120 Red Carpet Ln,Los Angeles,CA

Let's say we want only Connecticut CT employees. We could look for "CT" in the file.

$awk '/CT/ {print $0}' empf
300,Doe John,90000,1005 Royal Dr,Hartford,CT
700,Bell Amy,60000,201 Winner CT,Atlanta,GA

To check for a pattern strictly against a field, we can use tilde operator "~"

$awk -F, '$6 ~ /CT/ {print $0}' empf
300,Doe John,90000,1005 Royal Dr,Hartford,CT

On a similar note, to exclude all the CA employees.

awk -F, '$6 !~ /CA/ {print $0}' empf
300,Doe John,90000,1005 Royal Dr,Hartford,CT
400,Day Matt,85000,100 W 4th Ave,Seattle,WA
700,Bell Amy,60000,201 Winner CT,Atlanta,GA