使用键列加入两个csv

Question

I would like to join two files using the key column the name of the city. I want to join only the data of the cities that are repeated in both csv...

For example

File1.csv

London, 10,15
Rome, 12,18
Paris, 8, 16
Lissabon, 10,17

File2.csv

London, 11,16
Berlin, 13,19
Paris, 12,18
Lissabon, 11,19

Result I wish,

London,10,15,11,16 
Paris,8,16,12,18
Lissabon,10,17,11,19

How can I do it in bash?

Answer 1

bash has a join command, though it requires that the input be sorted:

$ join -j 1 -t ',' <(sort File1.csv) <(sort File2.csv)
Lissabon, 10,17, 11,19
London, 10,15, 11,16
Paris, 8, 16, 12,18

Answer 2

Using this awk :

awk -F, 'FNR==NR {a[$1]=$0;next} $1 in a{p=$1; sub(/^[^,]+, */, "");
         print a[p], $0}' OFS=, file1 file2
London, 10,15,11,16
Paris, 8, 16,12,18
Lissabon, 10,17,11,19