Possible to replace string if match string in two files? [closed]

Question

i am aware of this doable by sed but only limited to one string let me explain let better, lets say in file 1 we got something like this

tom,123456789
steve,1478321
jon,315457

and in the second file file

tania,148321
john,123456789

so if a string in the second file matches the value in the first it will replace the value in the first file. Note i stink in programming i know this is prrettyy much doable via python or something but im clueless in them

Answer 1

Assuming you want to replace the first field if the second field matches, then you could use something like this:

awk -F, 'NR==FNR {a[$2]=$1; next} $2 in a {$1=a[$2]} 1' OFS=, file2 file1
john,123456789
steve,1478321
jon,315457