按时间查询并统计数据库的问题

[tianzhejt]

procedure TForm1.Button1Click(Sender: TObject);
var
i:integer;
begin
with adoquery1 do
begin
Close;
SQL.Clear;
SQL.Text := 'select riqi,suxue from cheji ' +
'where riqi = ''' + FormatDateTime('yyyy-mm-dd',DateTimePicker1.DateTime) +''''
and ????????;
Open;
end;
end;

我要把DateTimePicker1选中的时间在dbgrid中显示出来，并且把数学这个字段下的所有数据求和，
该如何实现,请帮助。

[liuqifeiyu]

with adoquery1 do
begin
SQL.Text := 'select '+#39+FormatDateTime('yyyy-mm-dd',DateTimePicker1.DateTime) +#39+' as choseriqi,sum(suxue) as sumsuxue,riqi,suxue from cheji ' +
' where riqi = ''' + FormatDateTime('yyyy-mm-dd',DateTimePicker1.DateTime) +''''
and ????????
group by riqi,suxue';
Open;
end;

[xjjrocker]

SQL.Text := 'select riqi,suxue from cheji ' +
'where riqi = ''' + FormatDateTime('yyyy-mm-dd',DateTimePicker1.DateTime) +''''
and ????????;
=======不太明白你的意思，可能理解有误=========>
SQL.add('select riqi,sum(suxue) as 新栏位名 from cheji');
SQL.add('where riqi = FormatDateTime('yyyy-mm-dd',DateTimePicker1.DateTime)');

是这个意思吗，呵呵

[XueYan]

阿，你可以使用adoquery1动态创建字段，就是使用计算出来的字段

[tianzhejt]

and ?????? 这里就是我想要加的求和的语句。