oracle高效分页存储过程

create or replace package JT_P_page is
type type_cur is ref cursor;                    --定义游标变量用于返回记录集
procedure Pagination (Pindex in number,        --要显示的页数索引，从0开始
Psql in varchar2,        --产生分页数据的查询语句
Psize in number,         --每页显示记录数
Pcount out number,       --返回的分页数
Prowcount out number,    --返回的记录数
v_cur out type_cur      --返回分页数据的游标
);
end JT_P_page;
commit;
--定义包主体
create or replace package body JT_P_page is
procedure Pagination(Pindex in number, --要显示的页数索引，从0开始
Psql in varchar2, --产生分页数据的查询语句
Psize in number, --每页显示记录数
Pcount out number, --返回的分页数
Prowcount out number, --返回的记录数
v_cur out type_cur --返回分页数据的游标
) AS
v_sql VARCHAR2(1000);
v_Pbegin number;
v_Pend number;
begin
v_sql := 'select count(*) from (' || Psql || ')';
execute immediate v_sql into Prowcount; --计算记录总数
Pcount := ceil(Prowcount / Psize); --计算分页总数
--显示任意页内容
v_Pend := Pindex * Psize + Psize;
v_Pbegin := v_Pend - Psize + 1;
v_sql := 'select * from (select rownum rn,t.* from (' || Psql || ')t) where rn between ' || v_Pbegin || ' and ' || v_Pend;
open v_cur for v_sql;
end Pagination;
end JT_P_page;
commit;

*************************************************************
OracleParameter[] param = new OracleParameter[] { new OracleParameter("Pindex", OracleType.Number), new OracleParameter("Psql", OracleType.VarChar), new OracleParameter("Psize", OracleType.Number), new OracleParameter("Pcount", OracleType.Number), new OracleParameter("Prowcount", OracleType.Number), new OracleParameter("v_cur", OracleType.Cursor) };
param[0].Value = index;
param[1].Value = sql;
param[2].Value = pageSize;

param[0].Direction = ParameterDirection.Input;
param[1].Direction = ParameterDirection.Input;
param[2].Direction = ParameterDirection.Input;
param[3].Direction = ParameterDirection.Output;
param[4].Direction = ParameterDirection.Output;
param[5].Direction = ParameterDirection.Output;

DataSet ds = OracleHelper.ExecuteDataset(Form1.OracleConnString, CommandType.StoredProcedure, "JT_P_page.Pagination", param);

int pcount = int.Parse(param[3].Value.ToString());
int record = int.Parse(param[4].Value.ToString());

lb_pcount.Text = pcount.ToString();

dataGridView1.DataSource = ds.Tables[0];