Skeeve's advice on using placeholders is very sensible. However it is not simply a matter of efficiency or elegance but one of security. As your code stands right now it would be a simple matter for some bad person to give the query parameter 'id' a value such as: 


1) ; (drop table student

[download]
and your day would begin to take a turn for the worse.

Really you should be checking the values of 'id' you are using for validity and skipping any which are not purely digits. You probably also want to use the -T switch to Perl and DBI's 'Taint' option to cause DBI to croak if it is passed tainted data.

You might have something like this replacing your foreach loop: 

my $sql = 'DELETE FROM student where student_id = ?';
my $sth = $dbh->prepare($sql);
foreach my $id ( $cgi->param('id') )
{
    if ( $id =~ /^(\d+)$/ )
    {
        $id = $1;
        $sth->execute($id);
     }
}

[download]

/J\

In reply to Re: Delete multiple values from mysql db.. by gellyfish
in thread Delete multiple values from mysql db.. by kiat

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.