How to efficiently use awk?

alias as follows

# 打印指定列
awk_print(){
    awk -v n=${1:-1} '{print $n}'
}
# 按指定列分组统计
awk_group(){
    awk -v n=${1:-1} '{++A[$n]} END {for(k in A) print k, A[k]}'
}
# 忽略前几列
awk_after(){
    awk -v n=${1:-1} '{for(i=1;i<=$n;i++){$i=""};print $0}' 
}

Use Cases

Find docker container id

docker ps -a | grep nginx | awk_print 1 

Statistics tcp connection status

sudo netstat -pent | awk_group 6

Logs

cat vhost_error.log | awk_after 5