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Master Detail Records

Hi!

I am learning VB.Net programming and having some problem with master detail records. It works fine when I follow all the norms of master detail data entry i.e. when I insert a record in master table and save that record and then add the records in child table using grid then everything works fine and even the grid automatically displays the value of the field which is common in both the tables.

But the problem is that I've a situation in which I've to enter the master and details record at the same time. Actually I am creating a loan registration form, in which along with all other details of the loan, I have to enter the details of the guarantors, the number of guarantors depends on the amount of the loan taken. So whenever I will register a new loan I'll have to enter the guarantors detail at the same time in a datagridview control.

At the moment I am filling all the master table fields in the form, leaving details grid blank and then save that record, then I reopen that record in edit mode and then enter the child(Guarantor) records. But as it seems it is not a practical solution.

So please help me in this regard. I will be very very thankful to you.

Regards,

SHISHIR WAHI

Hi,

Actually this is just fine. All you have to do is to insert your master record first and then your child records after. But you must do this at the same time in your Save button. I think you are being confused here since your form would contain all of your inputs.

Or you can just have a temporary storage for your child records first. Then add it to your datatable after youve already added your master record.

BTW, are you using plain DataTables and DataSets? Or are you using Typed Datasets and binding your controls into it?

cheers,

Paul June A. Domag

Visit my Online Blog - http://webmag.mvps.org

Paul Domag

Hi.

Thanks for the reply. But I am still confused coz it should happen in the same way as you told, i.e master record should be entered first then all the child records should be entered and then when I press the SAVE button then master records should be saved first and then the child table should be updated, but its not happening, as soon as I enter the master record and then the first child record in the grid and move to next row it gives the error that the ForeignKeyConstraint FK_LoanReg_LReg requires the child key values to exist in the parent table, and all the fields in the grid are reset.

BTW I am using SQLDataAdapters and Datasets. The code I am using to update records are as follows:-

Public Sub UpdateDataSet()

Dim objDataSetChanges As Cooperative.dsGLoan = New Cooperative.dsGLoan()

Me.BindingContext(DsGLoan1, "LoanReg").EndCurrentEdit()

objDataSetChanges = CType(DsGLoan1.GetChanges, Cooperative.dsGLoan)

If (Not (objDataSetChanges) Is Nothing) Then

Try

Me.UpdateDataSource(objDataSetChanges)

DsGLoan1.AcceptChanges()

Catch eUpdate As System.Exception

Throw eUpdate

End Try