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Initialize Variable Using awk Expression

 
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# 1  
Old 06-10-2013
Initialize Variable Using awk Expression
Hello All,
What i am trying to do is read the input file delimited by pipe and do further logic like simulating the for loop but using awk not sure if this a right approach but as i was told doing "for i in `cat $file`" is an over kill so trying to replicate the same thing using awk script below. I am using bash shell and in the below awk expression i have 2 questions

1) Why print $1 is working but not echo $1?
2) How do i initialize or assign a value to the variable UNINUM like UNINUM=`print $1` or UNINUM=$1?

Code:
awk -F\| '
{
#       print "Provider: " $1, " Uninum: " $2, " Extract Date: " $3, " Loading Status: " $4
echo $1
print $1
#UNINUM=$1
echo $UNINUM
}
' "dwh_StageLoadEmail.lst"

dwh_StageLoadEmail.lst
Code:
710119|16|2012-09-30|COMPLETED
610000|16|2012-09-30|COMPLETED
710056|16|2012-09-30|COMPLETED

# 2  
Old 06-10-2013
The reason is because echo is not a valid awk statement but print is.

You can assign a shell variable to awk variable using -v option:
Code:
awk -v UNINUM="$1"

For further reference check Assignment Options
# 3  
Old 06-10-2013
ok i think i am doing wrong, i have a for loop in my shell script which reads a file as below, i am trying to implement the same logic using awk that is what i am trying to achive above in my awk script, is that possible !? may be not as awk,sed are extensions to shell just to format output,file,custom print etc..but shell is the one where you do your programming looping etc..please correct me if i am wrong!

Code:
for i in `cat "${GEN_PARAM_LIST1}"`
        do
        UNINUM=`echo $i | awk -F"|" '{print $1}'`
        PROVIDER=`echo $i | awk -F"|" '{print $2}'`
        EXTRACT_DT=`echo $i | awk -F"|" '{print $3}'`
        VER_NUM=`echo $i | awk -F"|" '{print $4}'`

sqlplus ......etc
done

# 4  
Old 06-10-2013
The approach that you are using is not recommended. Also using awk inside a shell for loop is an overkill.

Set the IFS to pipe | and read each fields into different variables using a shell while loop:
Code:
while IFS="|" read UNINUM PROVIDER EXTRACT_DT VER_NUM
do
        # action here
done < "${GEN_PARAM_LIST1}"

# 5  
Old 06-11-2013
Hello Yoda,
I am trying to assign a value to the awk variable but getting syntax error, i read the links you provided but don't find a proper example. Can you please help, thank you.

Code:
awk -F\| '
awk -v LOCATION=/var/tmp -v DATAFILE=xxxx.xml -v ARG1=$1
BEGIN {
print "Informatica Was Able To Successfully Load the XML Data File $LOCATION/$DATAFILE"
}
{
print "Provider: " $1, " Uninum: " $2, " Extract Date: " $3, " Loading Status: " $4
}
' OFS=, "/home/infrmtca/bin/log/dwh_StageLoadEmail.lst" | /usr/bin/mutt -s "Provider XML Data File Loaded Successfully" "${EMAIL_LIST}"

# 6  
Old 06-11-2013
Below lines should be replaced
Code:
awk -F\| '
awk -v LOCATION=/var/tmp -v DATAFILE=xxxx.xml -v ARG1=$1

with
Code:
awk -F\| -v LOCATION="/var/tmp" -v DATAFILE="xxxx.xml" -v ARG1="$1" '

This User Gave Thanks to Yoda For This Post:
Ariean
# 7  
Old 06-11-2013
Thank you i replaced it but i don't see those variables expanded.

Code:
awk -F\| -v LOCATION="/var/tmp" -v DATAFILE="xxxx.xml" '
BEGIN {
print "Informatica Was Able To Successfully Load the XML Data File" $LOCATION, $DATAFILE
}
{
print "Provider: " $1, " Uninum: " $2, " Extract Date: " $3, " Loading Status: " $4
}
' OFS=, "/home/infrmtca/bin/log/dwh_StageLoadEmail.lst" | /usr/bin/mutt -s "Provider XML Data File Loaded Successfully" "${EMAIL_LIST}"

Output:
Code:
Informatica Was Able To Successfully Load the XML Data File 
Provider: 925000, Uninum: 6, Extract Date: 2012-12-31, Loading Status: 7

---------- Post updated at 10:13 AM ---------- Previous update was at 10:04 AM ----------

Its working when i removed the $ symbol for those awk variables in the print statement. thank you.
 
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