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Perform a uniq and count on 2nd column

Hello,

I need to perform a unique and count of dups at the same time and it need to be done on the 2nd column in a file.

the delimiter is space, and the file looks like:

column1 column2
abc xyz.com
123 xyz.com
456 xyz.com
peter abc.com
John 123.com
Kyle amazon.com
George amazon.com

The out put to me should look like, something below:

3 xyz.com
1 abc.com
1 123.com
2 amazon.com

I need the uniqueness on column 2 and I want to count the number of occurrence also on column 2.

I tried "sort -u -k2 <filename>" but it does not give me the count of occurrence.

Any thoughts..... help with this is much appreciated.

Thanks,

How about this order of operations with suitable flags...

Code:

cut {field spec}| grep {drop heading}| sort | uniq {with count}| sort {count ordering}

Which produces this with your (literal) input file, and final sort added:

Code:

1 123.com

1 abc.com

2 amazon.com

3 xyz.com

I leave the options as an exercise...

Associative arrays are designed for this - can be done (simply) with one pass of the data in for example awk.

You got columns ... you use awk :)