I wrote this script that reads from one database and inserts into another one. What I need to do is to add error handling to the script. I would like for the script to do is to check if the record already exists and if it does then write to error log otherwise insert it. I don’t know how to write the code. I would appreciate if somebody could help me. Thanks in advance. 
use strict;
use warnings;
use DBI;
#use Win32::ODBC;
use DBD::ODBC;

# Global Variables
my @statement;    # Array of sql statements that will be used for Sql
my @data;        # Array of table rows read from Sybase
my @message;    # Array of error messages used for debugging Sql


# SQL Connection            
my $dbh = DBI->connect( "dbi:ODBC:RETQC_SQL", "", "",
  {RaiseError => 1, PrintError => 1, AutoCommit => 0} ) or
die "Unable to connect: ";#. $DBI::errstr . "\n";



# Sybase Connection
my $dbh2 = DBI->connect( "dbi:ODBC:BPSA", "", "",
  {RaiseError => 1, PrintError => 1, AutoCommit => 0} ) or
die "Unable to connect: ";#. $DBI::errstr . "\n";




 #Create the sql statement for Sybase and execute it
$sth = $dbh2->prepare("SELECT (dbo.tbookkeeping_trans.branch_cd + dbo.
+tbookkeeping_trans.account_cd)As AccountNo,
'TRI'as TransferFlag,'NCT' as TransferType, 'C' as RejectType, dbo.tbo
+okkeeping_trans.security_adp_nbr  as AdpNumber,
dbo.tbookkeeping_trans.share_trans_qty  as Shares,dbo.tbookkeeping_tra
+ns.processing_dt
FROM dbo.tbookkeeping_trans   
WHERE (dbo.tbookkeeping_trans.client_nbr='0030' AND dbo.tbookkeeping_t
+rans.entry_cd IN ('JNL', 'JRL', 'REC') AND
dbo.tbookkeeping_trans.branch_cd >'248') ORDER BY  1");
$sth->execute;




my $insh=$dbh->prepare("INSERT INTO ClearTransferData(AccountNo, Trans
+ferFlag, TransferType, RejectType, AdpNumber, Shares, ProcessingDate)
+ VALUES ( ?, ?, ?, ?, ?, ?, ? )");

eval {
  while((@data) = $sth->fetchrow_array) {
    $insh->execute(@data);
  }
};
if($@)
{
  print STDERR "The insert died: $@";
}
$dbh2->commit();
$dbh->commit();

 #Close the sql DB Connection
$dbh->disconnect;

 #Close the Sybase DB connection
$sth->finish;
$dbh2->disconnect;

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update (broquaint): added <code> tags

In reply to Error Handling by SamueD2

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