This works for me: 
#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

use DBI;

my ($dbname, $user, $password) = @ARGV;

my $db = 'DBI'->connect('dbi:Pg:dbname=' . $dbname, $user, $password,
                        {AutoCommit => 0});
$db->do('CREATE TABLE t (id INT, name TEXT)');
my $populate = $db->prepare('INSERT INTO t (id, name) VALUES (?,?)');
my $max = 250_000;
for my $i (0 .. $max) {
    $populate->execute($i, join "", map chr, map 64 + int rand 26, 1 .
+. 10);
    print "$i\r";
}

my $from = 0;
my $fetch = $db->prepare('SELECT * FROM t LIMIT ? OFFSET ?');
while ($from <= $max) {
    $fetch->execute(1000, $from);
    while (my @row = $fetch->fetchrow_array) {
        say join "\t", @row;
    }
    say '---';
    $from += 1000;
}
$db->disconnect;

[download]
map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to Re^3: Posgres batch read with DBI? by choroba
in thread Posgres batch read with DBI? by cormanaz

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