组合动态SQL的问题（100分）(100分)

我试图在客户端用http://134.45.8.106/tmp/h11.exe/sc?tablename=查询_关口局数据04
相应的服务器ACTION代码：
procedure TWebModule1.WebModule1WebActionItem2Action(Sender: TObject;
Request: TWebRequest; Response: TWebResponse; var Handled: Boolean);
var
str1,str2:string;
begin
try
database1.open;
query2.DatabaseName:=database1.DatabaseName;
query2.SQL.Clear;
str1:=request.QueryFields.Values['tablename'];
query2.SQL.Add('select * from '+str1+' where rownum<11');
str2:=query2.SQL.CommaText;
QueryTableProducer1.Query:=query2;
with QueryTableProducer1 do
begin
caption:='<h1>dfffgdf</h1>';
query2.Active:=true;;
response.Content:=QueryTableProducer1.Content;
query2.Close;
end;
except
on E: Exception do
response.Content:= E.Message+' '+str2;
end;
handled:=true;

//with
end;
执行后浏览器提示：
Query2: Parameter 'tabalename' not found
该怎么办？？？

str1:=request.QueryFields.Values[tablename];

>HIGOAL
这样肯定不对，语法错误！

http://134.45.8.106/tmp/h11.exe/sc?tablename=查询_关口局数据04
tablename不是你传过来的参数吗

uery2: Parameter 'tabalename' not found
~~~~~~~~~~~~~~~~????