delphi 编程 DBGrid 不显示内容Query中的

Question

procedure TForm1.Button1Click(Sender: TObject);
begin
form1.Query1.Close;
form1.Query1.SQL.Clear;
//
form1.Query1.SQL.Add('select claimno from c_claim where telephone = ''');
form1.Query1.SQL.Add(edit1.Text);
form1.Query1.SQL.Add(''' union select claimno from c_claim where mobile = ''');
form1.Query1.SQL.Add(edit1.Text);
form1.Query1.SQL.Add(''';');

//form1.Query1.SQL.Add('select claimno from c_claim where telephone= ''');
//form1.Query1.SQL.Append(edit1.Text +''' union select claimno from c_claim where mobile = ''');
//form1.Query1.SQL.Append(edit1.Text +''';');
//form1.edit2.text := form1.Query1.SQL.Text;

Try
Query1.Active;
Query1.Prepare;
Query1.Open;
Except
Query1.ExecSQL;
End;
form1.DBGrid1.Refresh;
end;

查询过后 DBGrid能显示claimno 这个字段 但是里面没有值
我在informix数据库里面看到是有值的

Answer 1

procedure TForm1.Button1Click(Sender: TObject);
begin
form1.Query1.Close;
form1.Query1.SQL.Clear;
//
form1.Query1.SQL.Add('select claimno from c_claim where telephone = ''');
form1.Query1.SQL.Add(edit1.Text);
form1.Query1.SQL.Add(''' union select claimno from c_claim where mobile = ''');
form1.Query1.SQL.Add(edit1.Text);
form1.Query1.SQL.Add('''');

//form1.Query1.SQL.Add('select claimno from c_claim where telephone= ''');
//form1.Query1.SQL.Append(edit1.Text +''' union select claimno from c_claim where mobile = ''');
//form1.Query1.SQL.Append(edit1.Text +'''');
//form1.edit2.text := form1.Query1.SQL.Text;

Try
Query1.Active;
Query1.Prepare;
Query1.Open;
Except
Query1.ExecSQL;
End;
form1.DBGrid1.Refresh;
end;

改成这样试试

Answer 2

把这两句注释掉看看
form1.Query1.SQL.Add(''' union select claimno from c_claim where mobile = ''');
form1.Query1.SQL.Add(edit1.Text);

Answer 3

主要debug思路，查询条件有没有问题

Answer 4

form1.Query1.SQL.Add('select claimno from c_claim where telephone = ''');
form1.Query1.SQL.Add(edit1.Text);
form1.Query1.SQL.Add(''' union select claimno from c_claim where mobile = ''');
form1.Query1.SQL.Add(edit1.Text);
form1.Query1.SQL.Add(''';');

改成以下写法：
var
ssql1:string;

ssql1:= ‘select claimno from c_claim where telephone = '''+ edit1.Text +’’’ union select claimno from c_claim where mobile = '''+ edit1.Text+’’’ ’;
form1.Query1.SQL.Add(ssql1);

如果还不行的话就要看看claimno的栏位长度，超过300好像DBGrid就显示不出来。。。