PHP实现的oracle分页函数实例

/**
 * 数据连接
 */
function connect($db_user,$db_pwd,$db_name,$db_nls)
{
 $this->dbh = oci_connect($db_user,$db_nls);
}
function getall($query,$start=0,$rows=-1)
{
 $this->dbh = emptyempty($this->dbh) ? $this->connect() : $this->dbh;
 $this->sth = oci_parse($this->dbh,$query);
 oci_execute($this->sth,OCI_DEFAULT) or $this->error($this->sth,$query);
 oci_fetch_all($this->sth,$res,$start,$rows,OCI_FETCHSTATEMENT_BY_ROW+OCI_ASSOC);
 return $res;
}
/**
* 获取分页数
*
* $query  string   查询语句
* $total  int    总条数
* $page  int    页数
* $rows  int    每页显示数
* @return integer  总行数
*/
function getpage($query,$total,$page,$rows=VAR_PAGENAV_ROWS)
{
 $start_row = ($page - 1) * $rows + 1;
 $start_row = $start_row > $total ? 1 : $start_row;
 $end_row  = $start_row + $rows - 1;
 $end_row  = $end_row > $total ? $total : $end_row;
 $query   = "SELECT * FROM ( SELECT ROWNUM as row_num,r.* FROM ( $query ) r WHERE ROWNUM <= $end_row ) WHERE $start_row <= row_num";
 return $this->getall($query);
}
/**
* 获取一个查询的总行数
*
* $string $sql 查询语句
*
* return integer 总行数
*/
function getcount($sql){
 $subSQL = 'select count(*) '.stristr($sql,'from');
 return $this->getone($subSQL);
}
function getone($query)
{
 $row = $this->getrow($query);
 if (is_array($row))
 $one = current($row);
 else
 $one = '';
 unset($row);
 return $one;
}
function getrow($query)
{
 if (false === stripos($query,'COUNT(')) {
 if (false === stripos($query,'WHERE')) {
 $query .= ' WHERE ROWNUM = 1';
 } else {
 $query .= ' AND ROWNUM = 1';
 }
 }
 $result = $this->getall($query,1);
 if (emptyempty($result))
 $row = array();
 else
 $row = $result[0];
 unset($result);
 return $row;
}

$total = $this->db->getcount($sql);
$result = $this->db->getpage($sql,$page_number);