How to count number of unique values of a field in a tab-delimited text file?

Question

I have a text file with a large amount of data which is tab delimited. I want to have a look at the data such that I can see the unique values in a column. For example,

Answer 1

You can make use of cut, sort and uniq commands as follows:

cat input_file | cut -f 1 | sort | uniq

gets unique values in field 1, replacing 1 by 2 will give you unique values in field 2.

Avoiding UUOC :)

cut -f 1 input_file | sort | uniq

EDIT:

To count the number of unique occurences you can make use of wc command in the chain as:

cut -f 1 input_file | sort | uniq | wc -l