If I want to create a simple master/detail relationship of one-to-many, it is easy:

Tables and fields:

Contact: [u]Code[/u], Name <-- Master table
Phone: [u]Number[/u], Contact (Contact is a foreign key) <-- Detail table

Contact TDataSource properties:
- DataSet: ContactDataset
- Name: ContactDataSource

Contact TSqlite3Dataset properties:
- Name: ContactDataset
- TableName: Contact

Phone TDataSource properties:
- DataSet: PhoneDataset
- Name: PhoneDataSource

Contact TSqlite3Dataset properties:
- Name: PhoneDataset
- TableName: Phone
- IndexFieldNames: Contact
- MasterFields: Code
- MasterSource: ContactDataSource

But, if I want to create a master/detail relationship of one-to-many with several foreign keys, how I do it?

For example I want to create this relationship:

Contact: [u]Code[/u], Name <-- Master table
Company: [u]Code[/u], Name <-- Master table
Phone: [u]Number[/u], Contact, Company (Contact and Company are foreigns keys) <-- Detail table

How I do it?

Best regards.
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Usuario An?nimo wrote

If I want to create a simple master/detail relationship of one-to-many, it is easy:

[]

What is the application design?
You will have a Contact grid and a Company grid in the same window sharing the same Phone table/grid?
Or you will have a window with Contact + Phone and other window with Company + Phone?

Luiz

I have three TDBGrids.

Phone has two foreigns keys: Contact and Company.

2008/10/15 Luiz Americo Pereira Camara

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Usuario An?nimo wrote

I have three TDBGrids. Phone has two foreigns keys: Contact and Company.

The automatic master/source relationship provided by MasterSource property will not work in this case.
You will need to do manually.

- Clear the MasterSource/IndexFieldNames properties
- Create a procedure UpdatePhone and put

  PhoneDataset.Sql := 'Select * from PhoneTable where Contact = ' +
ContactDataset.FieldByName('IdField').AsString + ' And ' +
  'Company = ' + ContactDataset.FieldByName('IdField').AsString;
  PhoneDataset.Close;
  PhoneDataset.Open;

- Call UpdatePhone inside OnAfterScroll events of ContactDataset and CompanyDataset

Some refinement may be needed to handle corner cases (no contact etc)

Luiz