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in reply to Re^2: MongoDB replacing an array
in thread MongoDB replacing an array

And you're sure that @new is not empty at the point of the insert? Have you tried printing out its contents to be sure?

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Re^4: MongoDB replacing an array
by neilwatson (Priest) on Aug 26, 2012 at 18:10 UTC

      Okay, let's look at what you have.

      The MongoDB::Collection docs show that update takes three hash references (\%criteria, \%object and \%options).

      $col->update( { "host" => $host }, { '$set' => { "timestamp" => [ @new ] } }, { 'multiple' => 1, 'safe' => 1 } ) || die "$!";

      Your criteria is simply host = $host. Your object should set timestamp to the contents of @new. Your options include multiple which tells it to update all matching records and safe which causes it to croak on errors (so the || die you have is superfluous).

      Are you getting any errors or do the records just end up empty?

      Based on the docs, it looks right. So what's missing? We don't know. Without seeing more of the code, I don't think anyone will be able to help you.

        There is not much more to show. Most is boring data manipulation that leads to the final array. The array holds only numbers. Nothing embedded.

        my $conn = MongoDB::Connection->new; my $db = $conn->mydb || die "$!"; my ($col, $cols, @cols, $q, $doc, @b, @c, @new, $x, $date, $l, $host); + @cols = $db->collection_names; foreach $cols (@cols) {

        Above a loop through some collections and for each make the new array. Then I try to replace the array.

        if ( @new > 1 ){ foreach my $xxx (@new){ print '@new = '.strftime('%Y-%m-%d', l +ocaltime($xxx))."\n"; } $col->update( { "host" => $host }, { '$set' => { "timestamp" => @new } }, { 'multiple' => 1, 'safe' => 1 } ) || die "$!";

        The foreach loop above is just to show there is data in @new. That works :). The update fails. The documentation for MongoDB is a bit sparse. I assume my syntax is wrong. Alas, I cannot figure how.

        Neil Watson
        watson-wilson.ca