回家过年的最后一道难题了，数据分页。
我想做的是一个数据的分页面，在DBGrid中，做一button,下一页面，下一页面的显示。。
最好，做成存储过程，给个实例。要是连调用也SHOW出来，那再好不过了
[解决办法]
我的方案：SQL分页查询。ACCESS + ADOConnection + ADOQuery 测试通过。为答题接分而编的代码，一定不完美，楼主自行完善。
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, DB, ADODB, Grids, DBGrids;
type
TForm1 = class(TForm)
Conn: TADOConnection;
BtnConn: TButton;
DataSource1: TDataSource;
ADOQuery1: TADOQuery;
DBGrid1: TDBGrid;
BtnNext: TButton;
BtnFront: TButton;
BtnFirst: TButton;
procedure BtnConnClick(Sender: TObject);
procedure BtnNextClick(Sender: TObject);
procedure BtnFrontClick(Sender: TObject);
procedure BtnFirstClick(Sender: TObject);
private
{ Private declarations }
procedure PageFirst;//类方法
procedure PageScroll;//类方法
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
const
PerPage = 5; //每页显示5条记录
var
Page : integer = 1;
procedure TForm1.BtnConnClick(Sender: TObject);
begin
//ADOConnection连接，略
end;
procedure TForm1.PageFirst;
begin
with adoquery1 do
begin
close;
sql.Clear;
sql.Text := 'select top ' + IntToStr(PerPage) + ' * from 表 order by ID ';
open;
end;
Page := 1;
end;
procedure TForm1.PageScroll;
begin
with adoquery1 do
begin
close;
sql.Clear;
sql.Text := 'select top ' + IntToStr(PerPage) + ' * from 表 where ID not in (select top ' + IntToStr((Page) * PerPage) + ' ID from 表 order by ID) order by ID ';
open;
end;
end;
procedure TForm1.BtnFirstClick(Sender: TObject);//连接后，首先点击此“第一页”按钮
begin
PageFirst;
end;
procedure TForm1.BtnNextClick(Sender: TObject);//“下一页”
begin
PageScroll;
Inc(Page);
end;
procedure TForm1.BtnFrontClick(Sender: TObject);//“前一页”
begin
if Page = 0 then begin PageFirst; Page := 1; exit; end;
PageScroll;
Dec(Page);
end;
end.
[解决办法]
您需要找到一个分割标志。比如说关键字段作为分割标志，并且能够排序。
每一次的翻页记录下当前页面的最后一条记录的分割标志值。然后下一页。假设页面分割标志为id，select top 页面显示记录条数 * from tablename where id> Currentid 即可！
[解决办法]
大多使用select top加一些条件来实现的
[解决办法]
下面这个存储过程比较高效
CREATE PROCEDURE pagination
@tblName varchar(255), -- 表名
@strGetFields varchar(1000) = '* ', -- 需要返回的列
@fldName varchar(255)= ' ', -- 排序的字段名
@PageSize int = 10, -- 页尺寸
@PageIndex int = 1, -- 页码
@doCount bit = 0, -- 返回记录总数, 非 0 值则返回
@OrderType bit = 0, -- 设置排序类型, 非 0 值则降序
@strWhere varchar(1500) = ' ' -- 查询条件 (注意: 不要加 where)
AS
declare @strSQL varchar(5000) -- 主语句
declare @strTmp varchar(110) -- 临时变量
declare @strOrder varchar(400) -- 排序类型
if @doCount != 0
begin
if @strWhere != ' '
set @strSQL = "select count(*) as Total from [ " + @tblName + "] where "+@strWhere
else
set @strSQL = "select count(*) as Total from [ " + @tblName + "] "
end
--以上代码的意思是如果@doCount传递过来的不是0，就执行总数统计。以下的所有代码都是@doCount为0的情况
else
begin
if @OrderType != 0
begin
set @strTmp = " <(select min "
set @strOrder = " order by [ " + @fldName + "] desc "
--如果@OrderType不是0，就执行降序，这句很重要！
end
else
begin
set @strTmp = "> (select max "
set @strOrder = " order by [ " + @fldName + "] asc "
end
if @PageIndex = 1
begin
if @strWhere != ' '
set @strSQL = "select top " + str(@PageSize) + " "+@strGetFields+ " from [ " + @tblName + "] where " + @strWhere + " " + @strOrder
else
set @strSQL = "select top " + str(@PageSize) + " "+@strGetFields+ " from [ "+ @tblName + "] "+ @strOrder
--如果是第一页就执行以上代码，这样会加快执行速度
end
else
begin
--以下代码赋予了@strSQL以真正执行的SQL代码
set @strSQL = "select top " + str(@PageSize) + " "+@strGetFields+ " from [ "
+ @tblName + "] where [ " + @fldName + "] " + @strTmp + "([ "+ @fldName + "]) from (select top " + str((@PageIndex-1)*@PageSize) + " [ "+ @fldName + "] from [ " + @tblName + "] " + @strOrder + ") as tblTmp) "+ @strOrder
if @strWhere != ' '
set @strSQL = "select top " + str(@PageSize) + " "+@strGetFields+ " from [ "
+ @tblName + "] where [ " + @fldName + "] " + @strTmp + "([ "
+ @fldName + "]) from (select top " + str((@PageIndex-1)*@PageSize) + " [ "
+ @fldName + "] from [ " + @tblName + "] where " + @strWhere + " "
+ @strOrder + ") as tblTmp) and " + @strWhere + " " + @strOrder
end
end
exec (@strSQL)
GO
[解决办法]
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