Obtain paging data in Oracle

Obtain the DataSet value by page in Oracle.
Example:
/// <Summary>
/// Obtain the Colletion paging data
/// </Summary>
Public DataSet GetList (int PageIndex, int PageSize, string sortExpression, string strWhere)
{
StringBuilder sb = new StringBuilder ();
Sb. Append ("select *");
Sb. Append ("from (select COLLECTGOODSID, PURCHASENUM, COLLECTIONTAG, MEMBERID, T_WEB_GOODS. * from T_WEB_GOODS, T_WEB_COLLECTGOODS where T_WEB_GOODS.GOODID = login and ");
Sb. Append (strWhere );
Sb. Append (") temp ");
Sb. Append ("where rownum>" + (PageIndex-1) * PageSize + "and rownum <=" + (PageIndex-1) * PageSize + PageSize ));
DataSet ds = DbHelperOra. Query (sb. ToString ());
Return ds;
}
Use rownum <= (PageIndex-1) * PageSize to select the page number, and use (PageIndex-1) * PageSize + PageSize) to select the first few of the page.