In using the DataRowCollection::Find with the
NorthWind/Employees table, I'm getting an exception
stating that the table doesn't contain a primary key -
which it does (EmployeeID). Has anyone else run into
problems with this method?

"Tom Archer" <(E-Mail Removed)> wrote
> In using the DataRowCollection::Find with the
> NorthWind/Employees table, I'm getting an exception
> stating that the table doesn't contain a primary key -
> which it does (EmployeeID). Has anyone else run into
> problems with this method?

Tom,
In order to use the Find method, the DataTable object to which the
DataRowCollection object belongs to must have at least one column
designated as a primary key column.
http://msdn.microsoft.com/library/en...rykeytopic.asp

See the PrimaryKey property for details on creating a PrimaryKey column,
or an array of DataColumn objects when the table has more than one primary key.
http://msdn.microsoft.com/library/en...findtopic2.asp

--

Thanks,
Carl Prothman
Microsoft ASP.NET MVP
http://www.able-consulting.com

Thanks Carl.

Just to clarify that I'm understanding this correctly:

ADO.NET can't figure out that the underlying table has a
primary key so I must explicitly tell it which column is
the primary key?

"Tom Archer" <(E-Mail Removed)> wrote
> Just to clarify that I'm understanding this correctly:
>
> ADO.NET can't figure out that the underlying table has a
> primary key so I must explicitly tell it which column is
> the primary key?
>

Tom,
For an untyped DataSet, the primary key information is NOT filled in.
In this case, you'll need to specify which column(s) is the primary key.

However, for a Typed DataSet, then the primary key information
is filled in for you.

e.g.

// Untyped DataSet
DataSet dataSet = new DataSet();
sqlDataAdapter1.Fill(dataSet, "Employees");
int count1 = dataSet.Tables["Employees"].PrimaryKey.Length;
// count1 = 0

// Typed DataSet
EmployeesDataSet employeeDataSet = new EmployeesDataSet();
sqlDataAdapter1.Fill(employeeDataSet.Employees);
int count2 = employeeDataSet.Employees.PrimaryKey.Length;
// count2 = 1

--

Thanks,
Carl Prothman
Microsoft ASP.NET MVP
http://www.able-consulting.com

That was the missing piece to the puzzle. Thanks again,
Carl.

Tom,

Try using MIssingSchemaAction = ...AddWithKey on your DataAdapter.

--
Kathleen (MVP-VB)



"Tom Archer" <(E-Mail Removed)> wrote in message
news:044c01c3586b$a56d3b10$(E-Mail Removed)...
> In using the DataRowCollection::Find with the
> NorthWind/Employees table, I'm getting an exception
> stating that the table doesn't contain a primary key -
> which it does (EmployeeID). Has anyone else run into
> problems with this method?

>-----Original Message-----
>Tom,
>
>Try using MIssingSchemaAction = ...AddWithKey on your
DataAdapter.

Works like a charm. Thanks Kathleen.

"Carl Prothman [MVP]" <(E-Mail Removed)> wrote
> For an untyped DataSet, the primary key information is NOT filled in.
> In this case, you'll need to specify which column(s) is the primary key.
>

Or set the MissingSchemaAction before the Fill method:
sqlDataAdapter1.MissingSchemaAction = MissingSchemaAction.AddWithKey

--

Thanks,
Carl Prothman
Microsoft ASP.NET MVP
http://www.able-consulting.com