A recent chatterbox discussion made me aware that some otherwise cluefull people are not quite sure how to retrieve various perl data structures from a DBI query. Here's a simple example that illustrates the basics for Array of Arrays, Array of Hashes, and Hash of Hashes (all references). It should run with all DBDs. 

#!perl -w
use strict;
use DBI;
use Data::Dumper;
my $dbh=DBI->connect('dbi:AnyData(RaiseError=1):');
my($create,$populate,$query,$keyfield)=split /\n/,join '',<DATA>;
$dbh->do($_) for ($create,$populate);
print 'AoA ', Dumper $dbh->selectall_arrayref($query);
print 'AoH ', Dumper $dbh->selectall_arrayref($query,{Slice=>{}});
print 'HoH ', Dumper $dbh->selectall_hashref ($query,$keyfield);
__DATA__
CREATE TABLE x (id INTEGER, phrase VARCHAR(20))
INSERT INTO x (id,phrase) VALUES (1,'foo')
SELECT id,phrase FROM x
id

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In reply to Getting Perl Data Structures from DBI queries by jZed

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