You seem to be misunderstanding how grep works. I recommend re-reading the documentation.

You actually want something like this:

if ( grep $_ == $xpid, @procs ) { print "Pid is in use : $xpid\n"; }

Also, fetchrow_arrayref returns an array _reference_ (as in the name). So you should be writing:

$procs = $dbh->selectall_arrayref("select spid from v\$process"); if ( grep $_ == $xpid, @$procs ) { print "Pid is in use : $xpid\n"; }

The potential downside with grep is that it always searches the whole list - which will impact performance if the list is large. Something like this might be more efficient (or build a hash as robiticus suggests):

$procs = $dbh->selectall_arrayref("select spid from v\$process"); my $found; foreach (@$procs) { if ($_ == $xpid) { $found = 1; last; } } if ($found) { print "Pid is in use : $xpid\n"; }

Oh, and one last tip. If you use single quotes around your SQL then you don't need to escape the '$'.

$procs = $dbh->selectall_arrayref('select spid from v$process');
--
<http://dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg


In reply to Re: search an array by davorg
in thread search an array by Anonymous Monk

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.