Here's the benchmarking code (it's messy - code comments not welcome ;-)

use DBI;
use CDB_File;
use BerkeleyDB;
# use Benchmark   qw(timethese cmpthese);
use Benchmark   qw(timethese);

# do some setup
my $id_lit = 0;
my $id_lit2 = 0;
my $id_bdb = 0;
my $id_cdb = 0;
my $txt = 'a' x 100;

unlink("sqlite.test", "sqlite2.test", "bdb.test", "cdb.test");

my $dbh = DBI->connect('dbi:SQLite:dbname=sqlite.test','','',
               { AutoCommit => 1, RaiseError => 1 });
my $dbh2 = DBI->connect('dbi:SQLite:dbname=sqlite2.test','','',
               { AutoCommit => 0, RaiseError => 1 });
$dbh->do('CREATE TABLE test (id integer PRIMARY KEY, foo varchar(100))
+');
$dbh2->do('CREATE TABLE test (id integer PRIMARY KEY, foo varchar(100)
+)');
$dbh->do('PRAGMA default_synchronous = off');
my $sth_ins = $dbh->prepare('INSERT INTO test (id, foo) values (?, ?)'
+);
my $sth_sel = $dbh->prepare('SELECT foo FROM test where id=?');
my $sth2_ins = $dbh2->prepare('INSERT INTO test (id, foo) values (?, ?
+)');
my $sth2_sel = $dbh2->prepare('SELECT foo FROM test where id=?');

my %ch;
my $cdb = new CDB_File ('cdb.test', "cdb.test.$$") or die "Can't creat
+e";

my %bh;
my $bdb = tie %bh, 'BerkeleyDB::Hash',
                                    -Filename   => 'bdb.test',
                                    -Flags      => DB_CREATE,
                                    ;


sub insertLite {
    $id_lit++;
    $sth_ins->execute($id_lit, $txt);
}

sub insertLite2 {
    $id_lit2++;
    $sth2_ins->execute($id_lit2, $txt);
}

sub insertCDB {
    $id_cdb++;
    $cdb->insert($id_cdb, $txt);
}

sub insertBDB {
    $id_bdb++;
    $bh{$id_bdb} = $txt;
}

sub selectLite {
    $id_lit++;
    $sth_sel->execute($id_lit);
    1 while $sth_sel->fetch;
}

sub selectLite2 {
    $id_lit2++;
    $sth2_sel->execute($id_lit2);
    1 while $sth2_sel->fetch;
}

sub selectCDB {
    $id_cdb++;
    $ch{$id_cdb};
}

my $t1 = timethese(30_000,
                 {
                     'Insert SQLite'    => \&insertLite,
                     'Insert SQLite 2'  => \&insertLite2,
                     'Insert Berkeley'  => \&insertBDB,
                     'Insert CDB'       => \&insertCDB,
                 },
                 );

$dbh2->commit;
$cdb->finish;
$dbh->{AutoCommit} = 0;

$cdb = tie %ch, 'CDB_File', 'cdb.test' or die "tie failed: $!\n";

# cmpthese $t1;

$id_lit = 0;
$id_lit2 = 0;
$id_bdb = 0;
$id_cdb = 0;

my $t2 = timethese(30_000,
                 {
                     'Select SQLite'    => \&selectLite,
                     'Select SQLite 2'  => \&selectLite2,
                     'Select Berkeley'  => \&selectBDB,
                     'Select CDB'       => \&selectCDB,
                 },
                 );
# cmpthese $t2;
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