php oracle 分页函数

mysql有limit，分页的时候，我们可以用limit 30,40,而oracle没有limit，用其他的方法来代替－－rownum.

一，底层方法

/**
 * 数据连接
 */
function connect($db_user, $db_pwd, $db_name, $db_nls)
{
 $this->dbh = oci_connect($db_user, $db_pwd, $db_name, $db_nls);

}

function getall($query, $start=0, $rows=-1)
{
 $this->dbh = empty($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, 0, 1);
 if (empty($result))
 $row = array();
 else
 $row = $result[0];
 unset($result);
 return $row;
}

主要二个方法我写一点注释

二，调用方法

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

上面只是贴出部分代码，也是最核心的。