一个Query问题---急，请高手们帮我see在什么地方出错！！！------在线等候your help!

Question

implementation
procedure TForm2.search();//把最终查询结果显示到memeo中
var
        sFile:string; //图片存取路径和名称
begin
        num:=0;
        ZhName:='';
        JieName:='';
        try
              ZhName:=Query2.FieldByName('zh_name').AsString;
              JieName:=Query1.FieldByName('j_num').AsString;
              //Query1.First;
              count:= Query2.fieldbyname('JiLu_num').AsInteger;
              Query1.MoveBy(count);              while not Query2.Eof do
                        if  OK='0' then
                                if Query2.FieldByName('flag').AsString='0' then
                                        begin
                                                DBMemo1.Lines.Add(Query2.FieldByName('document').AsString);                                                Next;
                                                num:=num+1;
                                                count:=count+1;
                                                continue;
                                        end  //end flag 0
                                        else if Query1.fieldbyname('flag').AsString='1' then
                                                begin
                                                        OK:='1'; //修改显示暂停标志为1——暂停
                                                        sFile:=Query2.fieldbyname('document').AsString;//取要加载的图片的路径和名称
                                                        Image1.Picture.LoadFromFile(sFile);   //动态加载.bmp图片
                                                        showmessage('如右图所示');
                                                        num:=num+1;
                                                        count:=count+1;
                                                end  //end flag 1
                                                else if Query2.fieldbyname('flag').AsString='3' then
                                                        begin
                                                                 OK:='1';  //修改显示暂停标志为1——暂停
                                                                 PlayDocument.Enabled:=true;
                                                                 filename:='';
                                                                 filename:= Query2.fieldbyname('document').AsString;
                                                                 showmessage('要查看多媒体演示，请单击"多媒体演示"!');
                                                                 count:=count+1;
                                                                 num:=num+1;
                                                        end //end flag 3
                                                        else
                                                            showmessage('数据库中的标识符falg出错')
                                                else
                                                        break;      //break while        except
                showmessage('数据库出错！！');
        end //end 例外处理
end;{$R *.dfm}procedure TForm2.PlayDocumentClick(Sender: TObject);
begin
        ShellExecute(handle,'open',PChar(filename),'-s','',SW_SHOWNORMAL); //执行外部可执行文件（*.exe）
        OK:='0';    //修改可继续执行标记OK
        PlayDocument.Enabled:=false;
end;procedure TForm2.PriZHClick(Sender: TObject);  //上一章
var
        zhang,jie:string;
begin
     try
        table2.Open;
        table2.First;
        jie:=table2.fieldbyname('j_num').AsString ;
        table2.Close;
     except
        showmessage('访问时Table2出错！');
    end;
        zhang:=inttostr(strtoint(DBEdit_zhnum.Text)+1);        if strtoint(zhang)>0 then
        begin
                DBEdit_zhnum.Text:=zhang;
                DBEdit_jnum.Text:=jie;
                OK:='0';                Query1.Close;
                Query1.SQL.Clear;
                Query1.SQL.Add('select zhang_table.zh_name,jie_table.j_name,docu_table.JiLu_num,docu_table.flag,docu_table.document');
                Query1.SQL.Add('from zhang_table,jie_table,docu_table');
                Query1.SQL.Add('where docu_table.zh_num=zhang_table.zh_num and docu_table.j_num=jie_table.j_num');
                Query1.SQL.Add('order by docu_table.j_num');
                Query1.ExecSQL;
                Query2.ExecSQL;                search();
                DBEdit_zhangN.Text:=ZhName ;
                DBEdit_jieN.Text:=JieName;
        end
        else showmessage('目前为第一章');
end;procedure TForm2.PriJieClick(Sender: TObject); //上一节
var
        zhang,jie:string;
begin
   try
       table2.Open;
       table2.Prior  ;
       jie :=table2.fieldbyname('j_num').AsString;
       zhang:=table2.fieldbyname('zh_num').AsString;
       table2.Close;
   except
        showmessage('访问时Table2出错！');
    end;       DBEdit_zhnum.Text:=zhang;
       DBEdit_jnum.Text:=jie;
       if zhang=DBEdit_zhnum.Text then
       begin
                Query1.Close;
                Query1.SQL.Clear;
                Query1.SQL.Add('select zhang_table.zh_name,jie_table.j_name,docu_table.JiLu_num,docu_table.flag,docu_table.document');
                Query1.SQL.Add('from zhang_table,jie_table,docu_table');
                Query1.SQL.Add('where docu_table.zh_num=zhang_table.zh_num and docu_table.j_num=jie_table.j_num');
                Query1.SQL.Add('order by docu_table.j_num');
                Query1.ExecSQL;
                Query2.ExecSQL;                OK:='0';  //修改暂停标志                search();
                DBEdit_zhangN.Text:=ZhName ;
                DBEdit_jieN.Text:=JieName;
       end
       else   showmessage('目前为本章第一节');
end;
//以下还有类似的“下一节”按钮操作
 
procedure TForm2.studyClick(Sender: TObject);  //学习
var
        zh_num,j_num:string;
begin
        OK:='0';
        zh_num:=DBEdit_zhnum.Text;
        j_num:=DBEdit_jnum.Text;        Query1.Close;
        Query1.SQL.Clear;
        Query1.SQL.Add('select zhang_table.zh_name,jie_table.j_name,docu_table.JiLu_num,docu_table.flag,docu_table.document');
        Query1.SQL.Add('from zhang_table,jie_table,docu_table');
        Query1.SQL.Add('where docu_table.zh_num=zhang_table.zh_num and docu_table.j_num=jie_table.j_num');
        Query1.SQL.Add('order by docu_table.j_num');
        Query1.ExecSQL;
        Query2.ExecSQL;        search();
        DBEdit_zhangN.Text:=ZhName ;
        DBEdit_jieN.Text:=JieName;
end;
 
 end.

Answer 1

SQL语句为：
select zhang_table.zh_name,jie_table.j_name,docu_table.JiLu_num,docu_table.flag,docu_table.document
from zhang_table,jie_table,docu_table
where docu_table.zh_num=zhang_table.zh_num and docu_table.j_num=jie_table.j_num
and docu_table.zh_num=:zhang and docu_table.j_num=:jie
order by docu_table.j_num执行部分是：
Query1.Close;
Query1.ParamByName('zhang').Value:=DBEdit_zhnum.Text;
Query1.ParamByName('jie').Value:=DBEdit_jnum.Text;
Query1.Prepare;
Query1.ExecSQL;if query1.RecordCount>0 then  //但是执行到这儿时，数据源自动关闭？？？？？？？？？
       ResultSearchShow();

Answer 2

Query1.ExecSQL;
改为
Query1.Open;

Answer 3

如果是select语句的话，最后要用query.open；或query.active:=true;如果是insert、update、delete语句才用execsql;

Answer 4

用Query1.open, ExecSQL是针对没有返回值的.Delphi帮助里说得很清楚:
Note: For SELECT statements, call Open instead of ExecSQL.

Answer 5

该成Query1.open后，却出现XXX.exe raised exception class EDBEngineError with message 'Insufficient memory for this operation.
......前些天就遇到这种情况，？？？？？？？？

Answer 6

你{$R *.dfm}的位置不对呀。应该在implementation的下面一行。

Answer 7

哦，刚才试了一下，  {$R *.dfm}的位置好像在哪无所谓。

Answer 8

“procedure TForm2.search();//把最终查询结果显示到memeo中”是自己定义的方法，delphi7的一般方法在具体实现时是放在implementation与{$R *.dfm}之间..............................

Answer 9

while not Query2.Eof do
                        if  OK='0' then
                                if Query2.FieldByName('flag').AsString='0' then
                                        begin
                                                DBMemo1.Lines.Add(Query2.FieldByName('document').AsString);                                                Next;
                                                num:=num+1;
                                                count:=count+1;
      ＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊continue;＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊這處是用來做什麼的？、、

Answer 10

我整理了一下不过不太明白楼主要做的目的，所以没有改动程序
在代码中，加入我的疑问unit Unit2;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, Mask, DBCtrls, DBTables, ExtCtrls, StdCtrls, DB;type
  TForm2 = class(TForm)
    Query1: TQuery;
    Query2: TQuery;
    PlayDocument: TButton;
    PriZH: TButton;
    DBMemo1: TDBMemo;
    Image1: TImage;
    Table1: TTable;
    Table2: TTable;
    DBEdit_zhnum: TDBEdit;
    PriJie: TButton;
    study: TButton;
    DBEdit_jnum: TDBEdit;
    DBEdit_zhangN: TDBEdit;
    DBEdit_jieN: TDBEdit;
    procedure PlayDocumentClick(Sender: TObject);
    procedure PriZHClick(Sender: TObject);  //上一章
    procedure PriJieClick(Sender: TObject); //上一节
    procedure studyClick(Sender: TObject);  //学习
  private
    { Private declarations }
  public
    { Public declarations }
    procedure search();
  end;var
  Form2: TForm2;implementation{$R *.dfm}var
  num, count: Integer;
  ZhName,JieName:string;
  OK, filename: string;procedure TForm2.search();//把最终查询结果显示到memeo中
var
  sFile:string; //图片存取路径和名称
begin
  num:=0;
  ZhName:='';
  JieName:='';
  try
    ZhName:=Query2.FieldByName('zh_name').AsString;
    JieName:=Query1.FieldByName('j_num').AsString;
    //Query1.First;
    count:= Query2.fieldbyname('JiLu_num').AsInteger;
    Query1.MoveBy(count);
    //在while循环体中，当执行到Flag标识为'1'时，此循环将进入死循环
    //因为Query2没有Next语句
    while not Query2.Eof do
      if OK='0' then
        if Query2.FieldByName('flag').AsString='0' then
        begin
          DBMemo1.Lines.Add(Query2.FieldByName('document').AsString);          Next;
          num:=num+1;
          count:=count+1;
          continue;
        end  //end flag 0
        else if Query1.fieldbyname('flag').AsString='1' then
        begin
          OK:='1'; //修改显示暂停标志为1——暂停
          sFile:=Query2.fieldbyname('document').AsString;//取要加载的图片的路径和名称
          Image1.Picture.LoadFromFile(sFile);   //动态加载.bmp图片
          showmessage('如右图所示');
          num:=num+1;
          count:=count+1;
        end  //end flag 1
        else if Query2.fieldbyname('flag').AsString='3' then
        begin
          OK:='1';  //修改显示暂停标志为1——暂停
          PlayDocument.Enabled:=true;
          filename:='';
          filename:= Query2.fieldbyname('document').AsString;
          showmessage('要查看多媒体演示，请单击"多媒体演示"!');
          count:=count+1;
          num:=num+1;
        end //end flag 3
        else
          showmessage('数据库中的标识符falg出错')
        else
          break;      //break while  except
    showmessage('数据库出错！！');
  end //end 例外处理
end;
procedure TForm2.PlayDocumentClick(Sender: TObject);
begin
  ShellExecute(handle,'open',PChar(filename),'-s',
    '',SW_SHOWNORMAL); //执行外部可执行文件（*.exe）
  OK:='0';    //修改可继续执行标记OK
  PlayDocument.Enabled:=false;
end;procedure TForm2.PriZHClick(Sender: TObject);  //上一章
var
  zhang,jie:string;
begin
  try
    table2.Open;
    table2.First;
    jie:=table2.fieldbyname('j_num').AsString ;
    table2.Close;
  except
    showmessage('访问时Table2出错！');
  end;
  zhang:=inttostr(strtoint(DBEdit_zhnum.Text)+1);  if strtoint(zhang)>0 then
  begin
    DBEdit_zhnum.Text:=zhang;
    DBEdit_jnum.Text:=jie;
    OK:='0';    Query1.Close;
    Query1.SQL.Clear;
    Query1.SQL.Add('select zhang_table.zh_name,' +
                   'jie_table.j_name,docu_table.JiLu_num,' +
                   'docu_table.flag,docu_table.document');
    Query1.SQL.Add('from zhang_table,jie_table,docu_table');
    Query1.SQL.Add('where docu_table.zh_num=zhang_table.zh_num' +
                   ' and docu_table.j_num=jie_table.j_num');
    Query1.SQL.Add('order by docu_table.j_num');
    Query1.Open;
    Query2.Open; //Query2是否已经设置正确？    search();
    DBEdit_zhangN.Text:=ZhName ;
    DBEdit_jieN.Text:=JieName;
  end
  else showmessage('目前为第一章');
end;procedure TForm2.PriJieClick(Sender: TObject); //上一节
var
  zhang,jie:string;
begin
  try
    table2.Open;      //当执行table2.Oepn后,数据集的指针指向First
    table2.Prior  ;   //所以当执行这条语句的时候会出错
    jie :=table2.fieldbyname('j_num').AsString;
    zhang:=table2.fieldbyname('zh_num').AsString;
    table2.Close;
  except
    showmessage('访问时Table2出错！');
  end;  DBEdit_zhnum.Text:=zhang;
  DBEdit_jnum.Text:=jie;
  if zhang=DBEdit_zhnum.Text then
  begin
    Query1.Close;
    Query1.SQL.Clear;
    Query1.SQL.Add('select zhang_table.zh_name,' +
                   'jie_table.j_name,docu_table.JiLu_num,'+
                   'docu_table.flag,docu_table.document');
    Query1.SQL.Add('from zhang_table,jie_table,docu_table');
    Query1.SQL.Add('where docu_table.zh_num=zhang_table.zh_num' +
                   ' and docu_table.j_num=jie_table.j_num');
    Query1.SQL.Add('order by docu_table.j_num');
    Query1.Open;
    Query2.Open;    OK:='0';  //修改暂停标志    search();
    DBEdit_zhangN.Text:=ZhName ;
    DBEdit_jieN.Text:=JieName;
  end
  else   showmessage('目前为本章第一节');
end;
//以下还有类似的“下一节”按钮操作procedure TForm2.studyClick(Sender: TObject);  //学习
var
  zh_num,j_num:string;
begin
  OK:='0';
  zh_num:=DBEdit_zhnum.Text;
  j_num:=DBEdit_jnum.Text;  Query1.Close;
  Query1.SQL.Clear;
  Query1.SQL.Add('select zhang_table.zh_name,' +
                 'jie_table.j_name,docu_table.JiLu_num,' +
                 'docu_table.flag,docu_table.document');
  Query1.SQL.Add('from zhang_table,jie_table,docu_table');
  Query1.SQL.Add('where docu_table.zh_num=zhang_table.zh_num' +
                 ' and docu_table.j_num=jie_table.j_num');
  Query1.SQL.Add('order by docu_table.j_num');
  Query1.Open;
  Query2.Open;  search();
  DBEdit_zhangN.Text:=ZhName ;
  DBEdit_jieN.Text:=JieName;
end;
 
end.

Answer 11

to all:
目的是对三个表进行查询，并显示查询结果：表中的内容有文本、读取图片的路径和读取动化文件的路径，当读到图片时停一下，提示用户有图片，等用户确定后继续往下显示内容，读到有动化文件时也停一下，提示用户...........
(修改后如下，请各位多提宝贵意见)
unit form3;
interface
uses
.........
type
   procedure PlayDocumentClick(Sender: TObject);//播放动化文件
    procedure zhqDSSearch();//查询章号和章名
    procedure jqDSSearch();//查询节号和节名
    procedure DSSearch();//查询上面查到的相应内容
    procedure ResultSearchShow();//显示查询结果
.......
implementation
procedure TForm2.zhqDSSearch();          //查找相应的章
begin
        try
                zhq.Close;
                zhq.ParamByName('zhang').Value:=DBEdit1.Text;
                zhq.Prepare;
                zhq.Open;
        except
                showmessage('查找章名时出错！');
        end;
end;
procedure TForm2.jqDSSearch();        //查找相应的节
begin
        try
                jq.Close;
                jq.ParamByName('zhang').Value:=DBEdit1.Text;
                jq.Prepare;
                jq.Open;
        except
                showmessage('查找节名时出错！');
        end;
end;procedure TForm2.DSSearch();
begin
        try
                Query1.Close;
                Query1.ParamByName('zhang').Value:=DBEdit1.Text;               Query1.ParamByName('jie').Value:=DBEdit2.Text;                Query1.Prepare;
                Query1.Open;
          except           showmessage('查询有误');          end;end;
procedure TForm2.ResultSearchShow();//把最终查询结果显示到memeo中
var
        sFile:string; //图片存取路径和名称
begin
        num:=0;        try
              while not Query1.Eof do
                        if  OK='0' then
                                begin
                                if Query1.FieldByName('flag').AsString='0' then
                                        begin
                                                DBMemo1.Lines.Add(Query1.FieldValues['document']);
                                               //Memo1.Lines.Add(Query1.FieldByName('document').AsString);
                                                Query1.Next;                                                num:=num+1;
                                                count:=count+1;
                                                continue;
                                        end  //end flag 0
                                        else if Query1.FieldByName('flag').AsString='1' then
                                                begin
                                                        OK:='1'; //修改显示暂停标志为1——暂停
                                                        sFile:=Query1.fieldbyname('document').AsString;//取要加载的图片的路径和名称
                                                        Image1.Picture.LoadFromFile(sFile);   //动态加载.bmp图片
                                                        showmessage('如右图所示');                                                        Query1.Next;
                                                        num:=num+1;
                                                        count:=count+1;
                                                end  //end flag 1
                                                else if Query1.fieldbyname('flag').AsString='3' then
                                                        begin
                                                                 OK:='1';  //修改显示暂停标志为1——暂停
                                                                 PlayDocument.Enabled:=true;
                                                                 filename:='';
                                                                 filename:= Query1.fieldbyname('document').AsString;
                                                                 showmessage('要查看多媒体演示，请单击"多媒体演示"!');                                                                Query1.Next;
                                                                count:=count+1;
                                                                 num:=num+1;
                                                        end //end flag 3
                                                        else                                  showmessage('数据库中的标识符falg出错')
                        end
                        else
                                                        break;      //break while        except
                showmessage('数据库出错！！');
        end; //end 例外处理
end;{$R *.dfm}
..........（但感觉代码并不是最优，显得罗嗦，原来的使用表关联查询.....）