Hi Guys...
I am newbie to awk and would like a solution to probably one of the simple practical questions.

I have a test file that goes as:

1,2,3,4,5,6
7,2,3,8,7,6
9,3,5,6,7,3
8,3,1,1,1,1
4,4,2,2,2,2

I would like to know how AWK can get me the distinct values say for eg: on col2 and figure out that the distinct values are only 2,3,4.
I need to check my actual realtime medical file with the distinct service dates from around a relatively big 200,000 records.

And one more question is...how can I use awk to print out records which dont meet a specific criteria...like...
Eg: I want to see only those records where Distinct Col2 values are less than 10 and see the actual distinct values to figure out why they are < 10

I know I can always go for some fancy ETLs to achieve complex requirements(ofcoz this requirement is not complex anyway) and play around with the data but I wanna use the power of awk/sed to accomplish the tasks.

Help is highly appreciated.
Thank you very much
-Anduzzi

Cud someone help me on this pls?...

Thanks !!!

Using just shell script,

cut -d , -f2 file | sort | uniq

awk -F , '{ a[$2]++ } END { for (b in a) { print b } }' file

awk:

col=$1
nawk -v col="$col" 'BEGIN{FS=","}
{
	arr[$col]++
}
END{
print "Column "col" has distinct value:"
for (i in arr)
print i
}' file

$col=shift;
open(FH,"<file");
while(<FH>){
	@arr=split(",",$_);
	$hash{$arr[$col-1]}++;
}
close(FH);
print "Colum $col has distinct value:\n";
for $key (keys %hash){
	print $key,"\n";
}

The Perl can be even more succinctly expressed as a one-liner.

perl -laF, -ne '{ $a{$F[1]}++ } END { print for keys %a }' file

Hi Guys...
Thank you(era and cherry) very much for the solutions...I could use the array solution for my requirement.

Well, how abt incorporating a specific condition in AWK to retrieve such records which DONT meet the criteria as mentioned in my original post?...any thoughts ?...

-Anduzzi

Print lines where column 2 < 10

awk -F, '$2<10' file

awk -F, '!($2<10)' file