Your example using placeholders (or bind variables - they are the question marks): 
my $sth = $dbh->prepare(<<sqlend

   insert into url_connect (sourceIP, dt, tm, remoteIP)
                    values (?, ?, ?, ?)
sqlend

# and then:
$sth->execute($sourceIP, $date, $time, $targetIP);

# and again:
$sth->execute($sourceIP2, $date2, $time2, $targetIP2);

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The idea is to prepare the query once and possibly execute it many times over, just supplying new values for the bind-variables.

The overhead of preparing the query on the database-server(parsing the sql, checking persmission, generating data-access paths etc) then just occurs once (and this is essential for scalability on systems like Oracle or DB2).

In reply to Re^3: Perl/SQL syntax error by morgon
in thread Perl/SQL syntax error by patt

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