카테고리를 매 월마다 새로 생성해서 글을 작성하는데요....

$write_table = $g5['write_prefix'] . $bo_table;
$sql = "
    select a.mb_id, b.mb_name, count(*) as cnt
      from {$write_table} a
               left outer join {$g5['member_table']} b on a.mb_id = b.mb_id
     where a.ca_name = '{$sca}'
     group by a.mb_id, b.mb_name
";

$result = sql_query($sql);

while ($row = sql_fetch_array($result)) {
    echo $row['mb_id'];
    echo $row['mb_name'];
    echo $row['cnt'];
    echo '<br>';
}