有关数据类型的问题？

Question

我的备注是采用ntext类型的当进行插入操作的时候，我在备注写2222是可以的，可是当我进行修改这条记录时，（其实备注的2222没被修改），它就提示我整数型不可以写入ntext型
我不明白为何连插入都成功，可是修改反而提示出错？？
附上我的代码：
//添加按钮的代码
procedure Tryxxfrm.Button2Click(Sender: TObject);
var
   YGBH,YGXM,BMBH,ZWBH,LXDH,DZYJ,BZ ,temp1,temp2,sqltext:string;
begin
  temp1:=combobox2.text;
  temp2:=combobox3.text;
 
  if((edit2.Text='')or(edit3.Text='')or(edit4.Text='')or(edit5.text='')or(combobox2.Text='')or(combobox3.text='') )then
      showmessage('请填写完整的信息')
      else
         begin
              with datamodulemis.adoquerybm do
              begin
              close;
              sql.clear;
              sql.Add('select bmbh from bm where bmm='+''''+temp1+'''');
              open;
              BMBH:=fieldbyname('bmbh').asstring;              end;
               with datamodulemis.adoqueryzw do
              begin
              close;
              sql.clear;
              sql.Add('select zwbh from zw where zwmc='+''''+temp2+'''');
              open;
              ZWBH:=fieldbyname('zwbh').asstring;              end;
              YGBH:=edit2.Text;
              YGXM:=edit3.Text;
              LXDH:=edit4.Text;
              DZYJ:=edit5.Text;
              BZ:=memo1.Text;
              sqltext:='Insert yg values('''+YGBH+''','''+YGXM+''','''+BMBH+''','''+ZWBH+''','''+LXDH+''','''+DZYJ+''','''+BZ+''')';
                with datamodulemis.adoqueryyg do
                begin
                   close;
                   sql.Clear;
                   sql.add(sqltext);
                   execsql;
                   showmessage('插入成功');
                end;          end;
//修改按钮的代码：
procedure Tryxxfrm.Button5Click(Sender: TObject);
   var
   YGBH,YGXM,BMBH,ZWBH,LXDH,DZYJ,BZ ,temp1,temp2,sqltext:string;
begin
  temp1:=combobox2.text;
  temp2:=combobox3.text;
 
  if((edit2.Text='')or(edit3.Text='')or(edit4.Text='')or(edit5.text='')or(combobox2.Text='')or(combobox3.text='') )then
      showmessage('请填写完整的信息')
      else
         begin
              with datamodulemis.adoquerybm do
              begin
              close;
              sql.clear;
              sql.Add('select bmbh from bm where bmm='+''''+temp1+'''');
              open;
              BMBH:=fieldbyname('bmbh').asstring;              end;
               with datamodulemis.adoqueryzw do
              begin
              close;
              sql.clear;
              sql.Add('select zwbh from zw where zwmc='+''''+temp2+'''');
              open;
              ZWBH:=fieldbyname('zwbh').asstring;              end;
              YGBH:=edit2.Text;
              YGXM:=edit3.Text;
              LXDH:=edit4.Text;
              DZYJ:=edit5.Text;
              BZ:=memo1.Text;
              sqltext:='update yg set ygxm ='+ YGXM+',lxdh='+LXDH+',dzyj='+DZYJ+',zwbh= '+ZWBH+',bmbh='+BMBH+',bz='+BZ+'where ygbh='+YGBH;
                with datamodulemis.adoqueryyg do
                begin
                   close;
                   sql.Clear;
                   sql.add(sqltext);
                   execsql;
                   showmessage('修改成功');
                end; 

Answer 1

sqltext:= 'update yg set ygxm = '+ QuotedStr(YGXM)+ ',lxdh= '+QuotedStr(LXDH)+ ',dzyj= '+QuotedStr(DZYJ)+ ',zwbh=  '+QuotedStr(ZWBH)+ ',bmbh= '+QuotedStr(BMBH)+ ',bz= '+QuotedStr(BZ)+ 'where ygbh= '+QuotedStr(YGBH);

Answer 2

sqltext:= 'update yg set ygxm = '+ QuotedStr(YGXM)+ ',lxdh= '+QuotedStr(LXDH)+ ',dzyj= '+QuotedStr(DZYJ)+ ',bmbh= '+QuotedStr(BMBH)+ ',bz= '+QuotedStr(BZ)+ 'where ygbh= '+QuotedStr(YGBH)+ ' and zwbh='+QuotedStr(Zwbh);