oracle学习 八 分页(使用rownumber)（持续更）

rownumber是查询的数据集之后加入一个伪列（连续的）使用它可以去制作以oracle数据库为基础的分页，语句类似于公式直接套用如下：

select * from (select rownum r,keycode from (select * from Acceptlist order by procid ))

where r between (pageindex-1)*pagesize +1 and pageindex*pagesize

其中pageindex为页码，pagesize为每页最多条数

oracle的between..and..前后都是闭区间，也就是说包含两个端的数.

多说一句的是：between and的相反的是not between..and，

not between..and..只是取指定范围的相反范围，也就是不在这个范围的记录，其用户可以用组个逻辑条件来取代。

between and 表示  >=  or <=，那么not between..and..就表示<  or  >。

 写成存储过程也可以这样

 

create or replace procedure proc_user_page

(

   v_pagesize in number,--一页有多少条数据

   v_pagenow  in number,--当前页码

   v_myrows out number,--总数据数

   v_mypage_count out number,--总页数

   p_cursor out testpackage.test_cursor--返回的结果集

)

is

v_sql varchar2(1000);



v_begin number:=(v_pagenow-1)*v_pagesize +1;--开始页数

v_end number:=v_pagenow*v_pagesize;--截止页数



begin



v_sql:='select * from (select rownum r,user_id from (select * from T_USER_INFO order by user_id ))

where r between '|| v_begin||' and '|| v_end;

--v_sql是执行SQL语句之后的一个结果集

--接下来需要使用游标读取结果集



open p_cursor 

for v_sql ;

  v_sql:='select count(*) from T_USER_INFO';

--执行v_sql，把值返回给v_rows

  execute immediate v_sql into v_myrows;

  if mod(v_myrows ,v_pagesize)=0

  then

    --总页数=总记录数/一页有多少条数据，如果有余数，就+1

  v_mypage_count:=v_myrows/v_pagesize;

  else



  v_mypage_count:=v_myrows/v_pagesize+1;

  end if;

  --为什么不能关闭？因为它是隐式游标。可以自动关闭

  --close p_cursor;

end;

 

 

 其中游标需要创建一个包：

create or replace package testpackage 

as 

    type test_cursor is ref cursor;

end testpackage ;

is ref cursor：相当于数据类型，不过是引用游标的数据类型。
这种变量通常用于存储过程和函数返回结果集时使用，因为PL/SQL不允许存储过程或函数直接返回结果集，但可以返回类型变量，于是引用游标的类型变量作为输出参数或返回值就应运而生了。

前台以及按钮的部分参考代码经过整理如下：

 <asp:Label ID="lblPage" runat="server" ></asp:Label>      

              <asp:LinkButton ID="lbnFirst" runat="Server" Text="首页"  CommandName="Page"

                  CommandArgument="First" onclick="lbnFirst_Click" ></asp:LinkButton>    

              <asp:LinkButton ID="lbnPrev" runat="server" Text="上一页" CommandName="Page"

                  CommandArgument="Prev" onclick="lbnPrev_Click"  ></asp:LinkButton>     

              <asp:LinkButton ID="lbnNext" runat="Server" Text="下一页" CommandName="Page"

                  CommandArgument="Next" onclick="lbnNext_Click" ></asp:LinkButton>   

              <asp:LinkButton ID="lbnLast" runat="Server" Text="尾页"  CommandName="Page"

                  CommandArgument="Last" onclick="lbnLast_Click" ></asp:LinkButton>     

              到第<asp:TextBox runat="server" ID="inPageNum" Width="25"></asp:TextBox>页

              <asp:Button ID="Button1" CommandName="go" runat="server" Text="go"

                  onclick="Button1_Click" />

              <br />  

protected void lbnPrev_Click(object sender, EventArgs e)

    {       

        pagecount = Convert.ToInt32(ViewState["page"]);

        pagecount--;

        ViewState["page"] = pagecount;

        Bind("test", 20, pagecount, "", "");

        lblPage.Text = "当前页：第" + pagecount + "页  共:" + info[0] + "页";

        if (pagecount == 1)

        {

            lbnFirst.Enabled = false;

            lbnPrev.Enabled = false;

            lbnNext.Enabled = true;

            lbnLast.Enabled = true;

        }

        else

        {

            lbnFirst.Enabled = true;

            lbnPrev.Enabled = true;

            lbnNext.Enabled = true;

            lbnLast.Enabled = true;

        }

    }

    protected void lbnNext_Click(object sender, EventArgs e)

    {

        pagecount = Convert.ToInt32(ViewState["page"]);

        pagecount++;

        ViewState["page"] = pagecount;

        if (pagecount == Convert.ToInt32(info[0]))

        {

            lbnFirst.Enabled = true;

            lbnPrev.Enabled = true;

            lbnNext.Enabled = false;

            lbnLast.Enabled = false;

        }

        else

        {

            lbnFirst.Enabled = true;

            lbnPrev.Enabled = true;

            lbnNext.Enabled = true;

            lbnLast.Enabled = true;

        }

        Bind("test", 20, pagecount, "", "");

        lblPage.Text = "当前页：第" + pagecount + "页 共:" + info[0] + "页";

    }

    protected void lbnFirst_Click(object sender, EventArgs e)

    {

        pagecount = 1;

        ViewState["page"] = pagecount;

        if (pagecount == 1)

        {

            lbnFirst.Enabled = false;

            lbnPrev.Enabled = false;

            lbnNext.Enabled = true;

            lbnLast.Enabled = true;

        }

        else

        {

            lbnFirst.Enabled = true;

            lbnPrev.Enabled = true;

            lbnNext.Enabled = true;

            lbnLast.Enabled = true;

        }

        Bind("test", 20, 1, "", "");

        lblPage.Text = "当前页:第1页 共:" + info[0] + "页";

    }

    protected void lbnLast_Click(object sender, EventArgs e)

    {

        pagecount = Convert.ToInt32(info[0]);

        ViewState["page"] = pagecount;

        Bind("test", 20, pagecount, "", "");

        lblPage.Text = "当前页:第" + pagecount + "页 共:" + info[0] + "页";

        if (pagecount == Convert.ToInt32(info[0]))

        {

            lbnFirst.Enabled = true;

            lbnPrev.Enabled = true;

            lbnNext.Enabled = false;

            lbnLast.Enabled = false;

        }

    }

    protected void Button1_Click(object sender, EventArgs e)

    {

        if (!string.IsNullOrEmpty(inPageNum.Text.Trim()))

        {

            Regex regex = new Regex(@"^\d+$");//验证是否为数字

            Match match = regex.Match(inPageNum.Text.Trim());

            if (match.Success)

            {

                pagecount = Convert.ToInt32(info[0]);

                if (Convert.ToInt32(inPageNum.Text.Trim()) <= 0)

                {

                    pagecount = 1;

                }

                else if (Convert.ToInt32(inPageNum.Text.Trim()) < pagecount)

                {

                    pagecount = Convert.ToInt32(inPageNum.Text.Trim());

                }

                Bind("test", 20, pagecount, "", "");

                lblPage.Text = "当前页:第" + pagecount + "页 共:" + info[0] + "页";

            }

            else

                Response.Write("<script>alert('只能输入正整数')</script>");

        }

    }

核心部分：

 protected void Page_Load(object sender, EventArgs e)

        {

            if (!IsPostBack) 

            {

                this.GridView1.DataSource = QuickPage(2, 2);

                this.GridView1.DataBind();

            }

        }



        public DataTable QuickPage(int v_pagesize, int v_pagenow)

        {

            OracleConnection conn = new OracleConnection(ConfigurationManager.ConnectionStrings["ApplicationServices"].ConnectionString);

            OracleCommand cmd = new OracleCommand();

            cmd.Connection = conn;

            cmd.CommandText = "proc_user_page";

            cmd.CommandType = CommandType.StoredProcedure;



            cmd.Parameters.Add("v_pagesize", OracleType.Number, 50);    //一页有多少条数据

            cmd.Parameters["v_pagesize"].Direction = ParameterDirection.Input;

            cmd.Parameters["v_pagesize"].Value = v_pagesize;



            cmd.Parameters.Add("v_pagenow", OracleType.Number);   //当前页码

            cmd.Parameters["v_pagenow"].Direction = ParameterDirection.Input;

            cmd.Parameters["v_pagenow"].Value = v_pagenow;



            cmd.Parameters.Add("v_myrows", OracleType.Number);  //总数据数

            cmd.Parameters["v_myrows"].Direction = ParameterDirection.Output;



            cmd.Parameters.Add("v_mypage_count", OracleType.Number);   //总页数

            cmd.Parameters["v_mypage_count"].Direction = ParameterDirection.Output;

            cmd.Parameters["v_mypage_count"].Value = 0;



            cmd.Parameters.Add("p_cursor", OracleType.Cursor);    //返回的结果集

            cmd.Parameters["p_cursor"].Direction = ParameterDirection.Output;

            



            DataSet Ds = new DataSet();

            OracleDataAdapter adapter = new OracleDataAdapter(cmd);

            adapter.Fill(Ds);

            conn.Close();



            //总记录数

           // RecordCount = int.Parse(cmd.Parameters["v_myrows"].Value.ToString());

            return Ds.Tables[0];

        }