1. SQL so close I can paste it
YAPC::NA::2011
Asheville
Brad Oaks
Plus Three, LP

2. printf
printf
'person_id %d name: %s',
$person_id,
$person->name;

3. printf with format as a variable
my $fmt = 'person_id %d name: %s';
printf
$fmt,
$person_id,
$person->name;

4. dynamically building a query
my (@conds, @binds);
my $joins = '';
my @uuids = $self->get_story_uuids;

5. add to your JOINs
if( @uuids ) {
$joins .= ' JOIN volunteer_form vf
ON(civ.volunteer_form_id =
vf.volunteer_form_id)';
}

6. add to your conditions
if( @uuids ) {
push(@conds, 'vf.story_uuid IN ( '
. join(', ', ('?') x scalar(@uuids)) . ')');
push(@binds, @uuids);
}

7. assemble WHERE clause
my $where = @conds
? ' WHERE ' . join(' AND ', @conds)
: '';

8. assemble the larger query
my $sql = qq/SELECT
COUNT(DISTINCT(civ.contact_info_id)) AS
volunteers
FROM contact_info_volunteer civ
JOIN contact_info ci ON (ci.contact_info_id
= civ.contact_info_id)
$joins $where
/;

9. prepare_cached
my $sth = $dbh->prepare_cached($sql);
$sth->execute(@binds);
my $data = $sth->fetchrow_hashref();
$sth->finish();

10. log the query
my $sth = $dbh->prepare_cached($sql);
my $sql_fmt = $sql;
$sql_fmt =~ s/?/'%s'/g;
warn sprintf $sql_fmt, @binds;

11. output in your logs (before)
SELECT
COUNT(DISTINCT(civ.contact_info_id)) AS volunteers
FROM contact_info_volunteer civ
JOIN contact_info ci ON (ci.contact_info_id = civ.contact_info_id)
JOIN volunteer_form vf ON(civ.volunteer_form_id = vf.volunteer_form_id)
WHERE vf.story_uuid IN ( ?, ?)
$VAR1 = ['1234','5678'];

12. output in your logs (after)
SELECT
COUNT(DISTINCT(civ.contact_info_id)) AS volunteers
FROM contact_info_volunteer civ
JOIN contact_info ci ON (ci.contact_info_id = civ.contact_info_id)
JOIN volunteer_form vf ON(civ.volunteer_form_id = vf.volunteer_form_id)
WHERE vf.story_uuid IN ( '1234', '5678')

13. log the query
my $sth = $dbh->prepare_cached($sql);
my $sql_fmt = $sql;
$sql_fmt =~ s/?/'%s'/g;
warn sprintf $sql_fmt, @binds;