Shell scripting question

I am new to unix, can someone explain what line is doing in the below code.

  echo "$1" "***FATAL*** EXCEPTIONS FOUND AT:" `date "+%e-%b-%Y %T"`|awk '{printf "%-30s%s %s %s %s %s %s\n",$1,$2,$3,$4,$5,$6,$7}'>>$tradehome/$log/summary.log


#!/bin/ksh -xv
#ods_fatal_check.sh started
#
fatal_count=`sqlplus -s $odsuser/$odspass @$tradehome/$plsql/endofday/start_ods_fatal_check.sql $1`; export fatal_count
   if ( test $fatal_count -ne 0)
   then
     echo "$1" "***FATAL*** EXCEPTIONS FOUND AT:" `date "+%e-%b-%Y %T"`|awk '{printf "%-30s%s %s %s %s %s %s\n",$1,$2,$3,$4,$5,$6,$7}'>>$tradehome/$log/summary.log
      $tradehome/$sh/ftp_summary_log.sh
      touch $tradehome/$log/odsfailed.dat
      exit
   fi
#ods_fatal_check.sh finished

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d27m11yAsked:
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simon3270Connect With a Mentor Commented:
$1 is the first parameter to the script.  The same value is passed to the start_ods_fatal_check.sql script in the "fatal_count=`...." line.

The line you are interested in first echos that $1 parameter, and the text "***FATAL*** EXCEPTIONS FOUND AT: DD-MMM-YYYY HH:MM:SS" (the current date and time).  awk takes that echoed line as input.  It prints out the first parameter (the $1 value) in a 30-character space, left-justified, and then prints out the remaining six words on the line (the "***FATAL***", "EXCEPTIONS", "FOUND" "AT:", the date and the time) with a single space between each string.  That formatted output is then appended to the $tradehome/$log/summary.log file.

One common confusion here is the two "$1"s.  The one immediately after the echo is the first parameter of the shell script.  The one after the "awk" is the first word on the input line being processed by awk.
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pony10usCommented:
There isn't enough information to be very detailed however a top level view of this line is that it puts an entry in the $tradehome/$log/summary.log file when there are "***FATAL*** EXCEPTIONS" found from running the script. If none are found then no entry is made.
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d27m11yAuthor Commented:
May I know what this awk is trying to do in the above shell

echo "$1" "***FATAL*** EXCEPTIONS FOUND AT:" `date "+%e-%b-%Y %T"`|awk '{printf "%-30s%s %s %s %s %s %s\n",$1,$2,$3,$4,$5,$6,$7}'>>$tradehome/$log/summary.log

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pony10usCommented:
awk '{printf "%-30s%s %s %s %s %s %s\n",$1,$2,$3,$4,$5,$6,$7}'>>$tradehome/$log/summary.log

this is the part that is telling it to print an entry in the log file.  

Please refer to this for an explanation as it will do a better job than me trying to type one out  :)  

http://www.gnu.org/software/gawk/manual/html_node/Printf-Examples.html
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d27m11yAuthor Commented:
This is very helpful.. thank you so much !
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pony10usCommented:
eloquently put simon.  I probably would have taken me writing a whole new book just to explain it as well as you did.   :)
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