Alrighty then. How do these two compare? (all strict, of course)

$stmt = "SELECT * FROM mytable WHERE id = $myid";
$sth= $dbh->prepare($stmt);
$sth->execute;
$results = $sth->fetchall_arrayref({});

__versus__

$stmt = "SELECT * FROM mytable WHERE id = $myid";
$results = $dbh->selectall_arrayref($stmt);
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Advantages of one over the other?

Note that you should probably use placeholders. It’s so easy with DBI that there’s rarely a reason not to.

my $stmt = "SELECT * FROM mytable WHERE id = ?";
my $sth = $dbh->prepare( $stmt );
$sth->execute( $myid );
my $results = $sth->fetchall_arrayref( {} );

# or

my $stmt = "SELECT * FROM mytable WHERE id = ?";
my $results = $dbh->selectall_arrayref( $stmt, undef, $myid );
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Then you can also further optimise the first case by saying

my $sth = $dbh->prepare_cached( $stmt );
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In that case, because the placeholder-adorned query is always the same, you might even end up preparing the statement only once during your entire runtime.

Makeshifts last the longest.

Interesting, I use placeholders 100% of the time when INSERTing, but didn't know there was an advantage to doing it with SELECT. My understanding was that placeholders helped to avoid sql injections.

So far, I'm hearing little difference in fetch vs select, other than the repeated-prepare-scenario.


—Brad
"The important work of moving the world forward does not wait to be done by perfect men." George Eliot