请高手帮忙详细解释下段代码
public function fetch_all_by_sql($where, $order = '', $start = 0, $limit = 0, $count = 0, $alias = '')
{
$where = $where && !is_array($where) ? " WHERE $where" : '';
if(is_array($order)) {
$order = '';
}
if($count) {
return DB::result_first('SELECT count(*) FROM '.DB::table($this->_table).' %i %i %i '.DB::limit($start, $limit), array($alias, $where, $order));
}
return DB::fetch_all('SELECT * FROM '.DB::table($this->_table).' %i %i %i '.DB::limit($start, $limit), array($alias, $where, $order));
}
public function fetch_all_by_sql($where, $order = '', $start = 0, $limit = 0, $count = 0, $alias = '')
{
$where = $where && !is_array($where) ? " WHERE $where" : '';
if(is_array($order)) {
$order = '';
}
if($count) {
return DB::result_first('SELECT count(*) FROM '.DB::table($this->_table).' %i %i %i '.DB::limit($start, $limit), array($alias, $where, $order));
}
return DB::fetch_all('SELECT * FROM '.DB::table($this->_table).' %i %i %i '.DB::limit($start, $limit), array($alias, $where, $order));
}
$order 同sql ORDER
$start 同sql 从哪一条记录开始返回
$limit 返回多少条记录
$count 是否直接返回搜索结果记录条数
alias 不太明白是个什么作用