two .csv files compare using awk

Question

I need to compare two files, File1.csv and File2.csv (Separated by ',') using Awk

Logic:

Column PID in both files are reference.

If for same 'PID' in 'File1.csv' and 'File2.csv' and in both files column 'Value' value is same then 'File2.csv' column 'UTS' value update for this column getting value from 'File1.csv' column 'RTS'.

Else for same 'PID' in 'File1.csv' and 'File2.csv' and in both files column 'Value' value is not same then 'File2.csv' column 'Value,RTS,UTS' value update for this column getting value from 'File1.csv' column 'Value,RTS,UTS'

File1.csv:

PID,Value,RTS
1,50,10:30:00
2,22,10:15:00
3,34,10:18:00
4,54,10:20:00
5,54,10:22:00
6,54,10:25:00
7,80,10:50:00
8,60,10:32:00
9,45,10:35:00

File2.csv:

PID,Value,RTS,UTS
1,12,10:10:00,10:14:00
2,22,10:15:00,10:17:00
3,34,10:18:00,10:19:00
4,54,10:20:00,10:21:00
5,54,10:22:00,10:24:00
6,54,10:25:00,10:29:00
7,60,10:30:00,10:31:00
8,60,10:32:00,10:34:00
9,45,10:35:00,10:35:00

Output:

PID,Value,RTS,UTS
1,50,10:30:00,10:30:00
2,22,10:15:00,10:15:00
3,34,10:18:00,10:18:00
4,54,10:20:00,10:20:00
5,54,10:22:00,10:22:00
6,54,10:25:00,10:25:00
7,80,10:50:00,10:50:00
8,60,10:32:00,10:32:00
9,45,10:35:00,10:35:00

Answer 1

Try this:

$ awk -F',' '
    FNR == NR {
        if (FNR == 1) {next}
        a[$1] = $2;
        b[$1] = $3;
        next;
    }
    {
        if (FNR == 1) {print;next}
        if (a[$1] == $2) {
            print $1,$2,$3,b[$1];
        }
        else {
            print $1,a[$1],b[$1],b[$1];
        }
    }
  ' OFS=',' file1,file2
PID,Value,RTS,UTS
1,50,10:30:00,10:30:00
2,22,10:15:00,10:15:00
3,34,10:18:00,10:18:00
4,54,10:20:00,10:20:00
5,54,10:22:00,10:22:00
6,54,10:25:00,10:25:00
7,80,10:50:00,10:50:00
8,60,10:32:00,10:32:00
9,45,10:35:00,10:35:00