数据库查询的问题

[jowers]

请大家帮忙看下.这段代码是否可以精简下.总感觉应该有比较好的写法.我的代码写得比较笨.
主要的问题是在comboobx1的选择上.如果选择大库,就查大库的库存,如果选择小库,就查小库的库存.如果选择全部.就查全部.
不知道有没有其它更简单的定法.望指教.




procedure Tform1.button1onclick(sender:Tobject);
begin
with adoquery1 do
begin
sql.clear;
if combobox1.Items.Text='大库' then begin
sql.add('select spdm,sum(sl) as sl from spkcb where ckdm=''大库'' group by spdm');
end else if combobox1.Items.Text='小库' then begin
sql.add('select spdm,sum(sl) as sl from spkcb where ckdm=''小库'' group by spdm');
end else begin
sql.add('select spdm,sum(sl) as sl from spkcb')
end;
end;

[gzmhero]

procedure TForm1.BitBtn1Click(Sender: TObject);
begin
    with adoquery1 do
    begin
        sql.clear;
        if combobox1.ItemIndex>=0 then
            sql.add('select spdm,sum(sl) as sl from spkcb')
        else
            sql.add('select spdm,sum(sl) as sl from spkcb where ckdm='''+combobox1.Items.Text+''' group by spdm');
    end;
end;

[JeffChung]

procedure Tform1.button1onclick(sender:Tobject); 
begin 
  with adoquery1 do 
  begin 
    sql.clear; 
    if combobox1.Items.Text='全部' then
      sql.add('select spdm,sum(sl) as sl from spkcb') 
    else
      sql.add('select spdm,sum(sl) as sl from spkcb where ckdm=' + 
                 QuotedStr(combobox1.Items.Text)+' group by spdm'); 
  end; 
end;

[gzmhero]

有点问题，不过写法还是类似这样。

Delphi(Pascal) code
procedure TForm1.BitBtn1Click(Sender: TObject);
begin
with adoquery1 do
begin
sql.clear;
if combobox1.Items.Text='' then
sql.add('select spdm,sum(sl) as sl from spkcb')
else
sql.add('select spdm,sum(sl) as sl from spkcb where ckdm='''+combobox1.Items.Text+''' group by spdm');
end;
end;
[/Quote]

[阿三]

procedure TForm1.BitBtn1Click(Sender: TObject);
var
vStr: String;
begin
vStr := ' select spdm,sum(sl) as sl from spkcb where 1=1';
if combobox1.Items.Text<>'' then
vStr := vStr +' and ckdm=:ckdm';
vStr := vStr +' group by spdm';
with adoquery1 do
begin
close;
sql.text := vStr;
if combobox1.Items.Text<>'' then
parameters.parambyname('chdm').value := combobox1.Items.Text;
Open;
end;
end;

[nanchangfantasy]

procedure TForm1.BitBtn1Click(Sender: TObject);
begin
with adoquery1 do
begin
sql.clear;
if combobox1.ItemIndex>=0 then
sql.add('select spdm,sum(sl) as sl from spkcb where ckdm='''+combobox1.Items.Text+''' group by spdm')

else sql.add('select spdm,sum(sl) as sl from spkcb')

end;
end;

[jowers]

[Quote=引用 1 楼 gzmhero 的回复:]
Delphi(Pascal) code
procedure TForm1.BitBtn1Click(Sender: TObject);
begin
with adoquery1 do
begin
sql.clear;
if combobox1.ItemIndex>=0 then
sql.add('select spdm,sum(sl) as sl from spkcb')
else
sql.add('select spdm,sum(sl) as sl from spkcb where ckdm='''+combobox1.Items.Text+''' group by spdm');
end;
end;
[/Quote]

这个比较精简一点.谢谢了.也谢谢其它答题的.每种方法都不错.我加点分一人分点吧.谢谢了.

[jowers]

现在竟然加不起来.明天结贴吧.还有.麻烦各位帮我再答个问题.已经提出来好几天了.一直没有人帮我解答.


http://topic.csdn.net/u/20080903/14/f9eae873-ed23-4d5e-9000-e8dda0634bc5.html


希望有高手帮我解答一下.dev才用.实在是有很多问题

[auqfiudh]

只有一个人带Open了 其它的人查出来怎么看啊

[jowers]

open;
close.这个不需要再说了.必竟我不是什么都不懂啊

[nieshiao]

procedure TForm1.BitBtn1Click(Sender: TObject);
begin
with adoquery1 do
begin
sql.clear;
if combobox1.ItemIndex>=0 then
sql.add('select spdm,sum(sl) as sl from spkcb')
else
sql.add('select spdm,sum(sl) as sl from spkcb where ckdm='''+combobox1.Items.Text+''' group by spdm');
end;
end;