datatable.import row bug/issue

[hharry]

hello all,

i have 2 datatables and am trying to transfer rows from datatable a to
datatable b
i use the datatable.importrow method.

the importrow method fails (but does not throw an exception) when
importing a datarow that has numeric columns. columns of type string
are imported fine.

e.g.

Dim objManualDataSet As DataSet
objMasterDataSet.Tables.Add(New DataTable(TableNames.Unique_DoB))

objMasterDataSet.Tables(TableNames.Unique_DoB).Columns.Add(New
DataColumn("dob_key", System.Type.GetType("System.String")))

objMasterDataSet.Tables(TableNames.Unique_DoB).Columns.Add(New
DataColumn("mn", System.Type.GetType("System.Int16")))

objMasterDataSet.Tables(TableNames.Unique_DoB).Columns.Add(New
DataColumn("dd", System.Type.GetType("System.Int16")))

objMasterDataSet.Tables(TableNames.Unique_DoB).Columns.Add(New
DataColumn("yy", System.Type.GetType("System.Int16")))

My 2nd dataset is generated by a call to a sql stored proc and has the
same structure as the 1st dataset..

My code to import the row is:

For Each objRow As DataRow In objManualDataSet.Tables(2).Rows
objMasterDataSet.Tables(TableNames.Unique_DoB).ImportRow(objRow)
Next

This is the result:

? objManualDataSet.Tables(2).Rows(0).ItemArray
{Length=4}
(0): "mn=1dd=12yy=1955"
(1): 1 {Short}
(2): 12 {Short}
(3): 1955 {Integer}
? objMasterDataSet.Tables(TableNames.Unique_DoB).Rows(0).ItemArray
{Length=4}
(0): "mn=3dd=29yy=1973"
(1): {System.DBNull}
(2): {System.DBNull}
(3): {System.DBNull}

Any ideas as to why cols 1, 2, 3 = System.DBNull ?

Thanks in advance

 

[Chris]

hello all,

i have 2 datatables and am trying to transfer rows from datatable a to
datatable b
i use the datatable.importrow method.

the importrow method fails (but does not throw an exception) when
importing a datarow that has numeric columns. columns of type string
are imported fine.

e.g.

Dim objManualDataSet As DataSet
objMasterDataSet.Tables.Add(New DataTable(TableNames.Unique_DoB))

objMasterDataSet.Tables(TableNames.Unique_DoB).Columns.Add(New
DataColumn("dob_key", System.Type.GetType("System.String")))

objMasterDataSet.Tables(TableNames.Unique_DoB).Columns.Add(New
DataColumn("mn", System.Type.GetType("System.Int16")))

objMasterDataSet.Tables(TableNames.Unique_DoB).Columns.Add(New
DataColumn("dd", System.Type.GetType("System.Int16")))

objMasterDataSet.Tables(TableNames.Unique_DoB).Columns.Add(New
DataColumn("yy", System.Type.GetType("System.Int16")))

My 2nd dataset is generated by a call to a sql stored proc and has the
same structure as the 1st dataset..

My code to import the row is:

For Each objRow As DataRow In objManualDataSet.Tables(2).Rows
objMasterDataSet.Tables(TableNames.Unique_DoB).ImportRow(objRow)
Next

This is the result:

? objManualDataSet.Tables(2).Rows(0).ItemArray
{Length=4}
(0): "mn=1dd=12yy=1955"
(1): 1 {Short}
(2): 12 {Short}
(3): 1955 {Integer}
? objMasterDataSet.Tables(TableNames.Unique_DoB).Rows(0).ItemArray
{Length=4}
(0): "mn=3dd=29yy=1973"
(1): {System.DBNull}
(2): {System.DBNull}
(3): {System.DBNull}

Any ideas as to why cols 1, 2, 3 = System.DBNull ?

Thanks in advance

I don't think you can do this. I seem to remember an issue that rows
can not be attached to two datatables at once. I could be wrong though.
Have you thought about cloning the datatable.

DataTable.Clone

 

[hharry]

Chris,

Yes, I tried using the Add method and got the row cannot belong to more
than one datatable error. The ImportRow method worlks fine if all
columns are of type string. I only get the error if any columns are
numeric.

 

[hharry]

here is my workaround:

For Each objRow As DataRow In objManualDataSet.Tables(2).Rows
Dim tmpRow(3) As Object
tmpRow(0) = objRow.Item(0)
tmpRow(1) = objRow.Item(1)
tmpRow(2) = objRow.Item(2)
tmpRow(3) = objRow.Item(3)

objMasterDataSet.Tables(TableNames.Unique_DoB).LoadDataRow(tmpRow,
True)
Next

 

[jayeldee]

You could try using something like this

objMasterDataSet.Tables(TableNames.Unique_DoB).Rows.Add(objRow.ItemArray)

in place of

objMasterDataSet.Tables(TableNames.Unique_DoB).ImportRow(objRow)

This call will depend on the Columns of both tables having the same
indexes or it will error (Mismatched data types) or worse - it will
copy the wrong data to the wrong columns.