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Wayne BarronFlag for United States of America

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ADO Table Relationships ( 3 Tables )

Hello All;

  It seems that when you are creating the MasterSource/MasterFields
Table Relationships between 3-Tables. That it will only allow you to do "2"
Tables this way.
   Is there a way to do "3" Tables?

   Reason For 3 Tables:

The Database Program that I have made to Admin my KB Web Site.
I need to have "3 Tables" Relationship together so that I can add to Master
Categories when inserting new records.

Anyway.
  Could someone please let me know how to do "3 Table Relationships in
Delphi"?

( P.S.
   Each of the Tables Fields are connected to "TDBEdits TDBMemos& TDBComboBox's"
   That I need to connect to. So when you click on a Field in the Main
Table.
   It needs to Display it's Relationship between the other Tables-Fields
   In the "TDBEdits TDBMemos& TDBComboBox's and so forth"
   And when creating new records in the Program, It needs to be able to
write
   To each of the Table-Fields the correct properties that are inserted or
chosen.)

Thank You All

Carrzkiss
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calinutz
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Did you try using SQL select? YOu can select even more tables together.

Something like  
select * from table1 t1, table2 t2, table3 t3 where t1.cod=t2.cod and t2.product=t3.product
or any other relationships.
You can use a Query Component as a Primary/Master dataset.
Then use the Primary/Master AfterScroll event to Close then reopen Secondary/Detail  Query Component(s) with parameters.

This example happens to be using ClientDataSets, however it works just as well with TQuery.
While this is not as auto-magic as w/ TTable components, you will have more control and network conflicts are less likely.

procedure TForm1.wwClientDataSet1AfterScroll(DataSet: TDataSet);
begin
  if ((PageControl1.ActivePageIndex <> 0)
  or not (wwClientDataSet1.RecordCount > 0)) then Exit;

  try
    // Drafting Deatil Info. ---------------------------------------
    with wwClientDataSet4, Params do begin

      Close;
      ParamByName('myDrawingRecord').Value := wwClientDataSet1Record_.AsString;
      Open;

      Panel2.Caption :=
        'Record ' + IntToStr(wwClientDataSet1.RecNo) +
        ' of ' + IntToStr(wwClientDataSet1.RecordCount);

      Edit1.Text := wwClientDataSet1.FieldByName('JOB_NUM').Text;
    end;

    // Job Info ------------------------
    with wwClientDataSet5, Params do begin
      if  (wwClientDataSet1JOB_NUM.AsString <> wwClientDataSet5JOB_NUM.AsString) then begin // Job Number Has Changed
        Close;
        ParamByName('myJobNumber').Value := wwClientDataSet1JOB_NUM.AsString;
        Open;
      end;


    end;

  except

  end;

end;
Avatar of Wayne Barron

ASKER

Thanks for your replies in this.
[Surfer Joe] thanks for the code.
Maybe I am tired or something, But I could not get
It to work? Sorry. Maybe if explained a little bit of what everything
Does, then maybe.

  Anyway.
  I have made a fully functional Demo.
Please download and take a look at it.
You will have to change to "Database" path in the ADOConnection
Located in the "DataModule = Form"

READ!
  The information that needs to be read is in the "PageControl [Content Tab] = "Choose" Title = ADO Table Relationships"
Please read the " Long Description" located in the " DBMemo"
Located at the bottom of the " ScrollBox "



http://www.carrz-fox-fire.com/Delphi/Database_Relationships.zip


Thank you all
Carrzkiss
If no one else comes in to assist in this question,
Then I will close this question, as it has been open for
Far to lond as it is.

Thank You
Carrz
ASKER CERTIFIED SOLUTION
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ee_ai_construct
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