UNIX for Dummies Questions & Answers

Hi all,
I am new to unix shell scripting and I am trying to append batch number that comes in Trailer record to the detailed record.

TR|20080312|22881 |000000005|20080319|2202
LN|20080312|077777722220 |0000100000017|ABS
LN|20080312|000799439326 |0000709943937|AA
TR|20080313|22897 |000000008|20080319|2202
LN|20080313|077777722220 |0000100000017|BCG
LN|20080313|603497005222 |0000600070057|ADXC
TR|20080314|22898 |000000011|20080319|2202
LN|20080314|077777722220 |0000100000017|kKAS
LN|20080314|603497005222 |0000600070057|adfras

This is how my data would be. I want to pull out Batch number i.e 4th column in the record that starts with TR and append it to first column of LN. This is one single file.

Filename=$1
grep '^TR' $Filename>A.txt
grep '^LN' $Filename>B.txt

#join -t"|" -1 2 -2 2 -0 1.4 A.txt B.txt >C.txt

cat B.txt | while read line
do
var=`echo $line | cut -d"|" -f2`
cat A.txt | while read value
do
val=`echo $value | cut -d"|" -f2`
val1=`echo $value | cut -d"|" -f4`
if [[ $var == $val ]]
then
line=$val1"|"$line
echo $line>>Apple.txt
fi
done
done

I tried the above code and its very very slow. The volume of records is from 2Mb to 60 MB.

Please adive. I think awk is faster but not sure how to do it in awk

Thanks
Kiran

You are looping over the entire file for every record? Whew!

You could at least optimize it to read only the matching lines.

Code:

grep "|$var|" A.txt | while read ...

But anyway, this is simple to do in awk, without any temporary file.

Code:

awk -F '|' '/^TR/{t = $4 }
/^LN/{printf "%s|%s\n", t, $0 }' "$1"

I hope I captured your requirements correctly. This assumes the TR always comes before the corresponding LN and that the LNs with the same number will always be immediately after the corresponding TR, and that there will be no LNs with other numbers before the next TR. It prints only the LNs, with field 4 from the previous TR tacked on at the front.

Hi
I would really appreciate it if you could tell me where to pass the file name. I have no clue.

Thanks
Kiran

I put $1 just like you had. Sorry, that's obviously pretty obscure. Replace that with the actual file name.

Hi,
Thanks for quick reponses.
I tried

awk -F '|' '/^TR/{t = $4 }
/^LN/{printf "%s|%s\n", t, $0 }' "temp.txt"

I am getting the following error.

awk: syntax error near line 1
awk: bailing out near line 1

Do you know what that means?

Thanks
Kiran

Hi,
I got it. I am using Sun solaris and I have to use nawk. It solved the issue.
your code worked like magic. Thanks a Bunch. Is there any way to remove unwanted spaces in that file?

Thanks
Kiran

Where there is a will, there is a way.

I assume you want the spaces before the separators out?

Code:

nawk -F '|' '/^TR/{t = $4 }
/^LN/{gsub (" +\|","|"); printf "%s|%s\n", t, $0 }' filename

Edit: silly me, there are no other spaces.

Just to recap, this captures $4 into t if this is a line starting with "TR". If it starts with "LN", it substitutes spaces followed by separator with just a separator, then prints the value of t followed by the whole current line.