Dear monks,

I need to iterate over a database table, and I need to process them in groups based on a key ("foo_id" in the example). What would be a good perlish way of getting them into an array for processing? Does DBI provide such a function?

This is what I came up with:

my $sth = $dbh->prepare(
  "SELECT foo_id, col1, col2 FROM a ORDER BY foo_id");
$sth->execute();

my @group;

while (my $row = $sth->fetchrow_hashref) {
  if (!@group or $row->{foo_id} == $group[0]->{foo_id}) {
    push @group, $row;
  } else {
    # print Dumper(\@group);
    process(\@group);
    @group = ($row);
  }
}

[download]

but I'm afraid it doesn't process the last group.

In reply to DBI & processing groups of rows by Anonymous Monk

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