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# 1  
Old 08-27-2013
Question awk logic

I am trying to check my logic on a long awk i'm using. I have about 30 checks that I built into an awk and I "believe" I did this right, but I could be wrong.

awk -F\| '
$9 !~ /\/*[0-9]{1,}*/
$9 ~ /\([A-Za-z]-[a-zA-Z0-9]{4}, [a-zA-Z0-9]{2,3}/
$9 ~ /\([A-Za-z0-9]{6}, [a-zA-Z0-9]{2,3}\)/
$9 ~ /\(\+[A-Za-z0-9]{5}, [a-zA-Z0-9]{2,3}\)/
$9 ~ /\(\+\+[A-Za-z0-9]{4}, [a-zA-Z0-9]{2,3}\)/
$9 ~ /\([A-Za-z0-9]{4}\+[A-Za-z0-9], [a-zA-Z0-9]{2,3}\)/
' file1.csv >> file2.csv

This is obviously just a subset to show the idea. My question is, when awk reads through my file, will it bail after the first match or will it continue down through each of my checks? Thanks!!
# 2  
Old 08-27-2013
It will run through all your checks, potentially printing the same line several times, and the first condition with the "not" will not stop it.

If you want this to be an or-condition, you could use an or-condition, like
($9 ~ /regex1) || ($9 ~ /regex2/) || ($9 ~ /regex3/)

to check multiple conditions but print only once.

How about this?

$9 !~ /\/*[0-9]{1,}*/ { next } # Skip lines containing  /91...
($9 ~ /regex1/) || ($9 ~ /regex2) ...' inputfile > outputfile

This User Gave Thanks to Corona688 For This Post:
# 3  
Old 08-27-2013
So if I understand you correctly, if I want it to bail, I can just add

to the end of each search string?
# 4  
Old 08-27-2013
By default, if you don't put { ... } after an expression, it assumes it should do { print }.

If you do { next } instead, it will skip to the next line without printing and start checking your expressions from the beginning instead.
This User Gave Thanks to Corona688 For This Post:
# 5  
Old 08-27-2013
Ok. Now what you said makes sense. I can skip the checks on records I don't want and then run all my checks after. Is there a limit on how many "||" I can do? Like I said, I have about 40 checks i'm doing per line.

Thank you so much for your helpful insights.
# 6  
Old 08-27-2013
Using or in regex

This User Gave Thanks to Jotne For This Post:
# 7  
Old 08-27-2013
Originally Posted by dagamier
Is there a limit on how many "||" I can do? Like I said, I have about 40 checks i'm doing per line.
Not really, but when you start piling them on like that it may be time to rethink your logic.

I forgot that awk supports | inside one regex like Jotne suggests, that will help.

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