linux 中 awk命令实现文件按列匹配

[root@pc1 test01]# ls
a.txt  b.txt
[root@pc1 test01]# cat a.txt
A:10
B:5
C:12
[root@pc1 test01]# cat b.txt
100 A
50 B
42 C
[root@pc1 test01]# awk -F "[: ]" '{if(NR == FNR) {ay[$1] = $2} else {print $2, $1, ay[$2]}}' a.txt b.txt
A 100 10
B 50 5
C 42 12

[root@pc1 test01]# ls
a.txt  b.txt
[root@pc1 test01]# cat a.txt
A:10
B:5
C:12
[root@pc1 test01]# cat b.txt
100 A
50 B
42 C
[root@pc1 test01]# awk -F "[: ]" '{if(NR == FNR) {ay[$1] = $2; next} {print $2, $1, ay[$2]}}' a.txt b.txt
A 100 10
B 50 5
C 42 12

[root@pc1 test01]# ls
a.txt  b.txt
[root@pc1 test01]# cat a.txt
A:10
B:5
C:12
[root@pc1 test01]# cat b.txt
100 A
50 B
42 C
[root@pc1 test01]# awk -F "[: ]" 'NR == FNR {ay[$1] = $2; next} {print $2, $1, ay[$2]}' a.txt b.txt
A 100 10
B 50 5
C 42 12