how to use AWK to print/filter data

I needed to just print out some columns in a file to see if I was missing something or not, so ... AWK to the rescue.

Some useful urls:

• Take nth column in a text file - I used the second answer by Tom van der Woerdt
• lots of good help here in How to use 'awk' to print columns from a text file (in any order) - this is where I got the field seperator
• 4 Awk If Statement Examples (if, if else, if else if, :? ) - forgot how to actually do a stand-alone awk script, so this was helpful. Also, how to use conditionals was another good thing.
• How To Use awk in Bash Scripting

Here is a simple command-line script to print the 2nd and 3rd column in a file:

awk '{ print $2 $3 }' myTextFile.txt

Of course, that didn't do what I wanted, as the file I was looking at was comma delimited, so ...

awk -F "," '{ print $2 $3 }' myTextFile.txt

That sort of did what I wanted (well, exactly, but too much data, so ...). Here is how to call it with using an AWK script file. Here is the file (called myAwkScript.awk):

{
    if ($3 == "" && $4 == "" ) {
        print $2 " : " $3 " - " $4;
    }
}

and to call it:

awk -F "," -f myAwkScript.awk myTextFile.txt

Then, as another example of trying to limit the data (as the above didn't print anything -- later I found out correctly):

{
    if ($2 == "" && ($3 != "AMER" && $3 != "ADVNCED")) { 
        print $1 " : " $2 " - " $3;
    }
}

then, I got something more like I needed.

So, anyway, AWK is a pretty handy way to filter out data when you need something quick.