Dear Monks,
I having problems understand why the following two snippets give different result (the second one being correct):
Situation: Arrayref with database rows, returned from subroutine, in my test-case 927306 rows: 
my $rowcache = runQuery($query,"Table",\@ids);
print "RunQuery results: ".scalar(@$rowcache)." rows\n";

[download]

Snippet one: Using while shift to return rows yields only 788425 resulting rows 
while (my $result = shift(@$rowcache) ) {   
   print OUT $result->{'id'}."\t".$result->{'Name'}."\t".$result->{'Co
+de'}."\t".$result->{'Date'}."\t".$result->{'Comment'}."\n";
}

[download]

Snippet two : Using foreach returns all rows: 
foreach my $result (@$rowcache)  {
    print OUT $result->{'id'}."\t".$result->{'Name'}."\t".$result->{'C
+ode'}."\t".$result->{'Date'}."\t".$result->{'Comment'}."\n";
}

[download]

I thought that these should be equivalent?
Best,
Geert

In reply to Different result for 'foreach' vs 'while shift' arrayref by gvandeweyer

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