Filter records from the dataset in vb.net

Question

I want to filter values from a dataset. It contain phone numbers starting with zero and non zero values. How can I filter a phone number (start with non zero no) from the dataset. Below is the vb.net code and the resulting error.

cmd = New OracleCommand("select  PHONE from  reports.renewal_contact_t where run_date=to_date('" + TextBox1.Text + "','mm/dd/yyyy') and  EXP_DATE =to_date('" + TextBox2.Text + "','mm/dd/yyyy') and  region not in('TNP')", cn)
ada = New OracleDataAdapter(cmd)
ada.Fill(ds, "reports.renewal_contact_t ")
Dim ds1 As New DataSet
ds1.Tables("reports.renewal_contact_t").DefaultView.RowFilter = "PHONE NOT like'0'"

Error: Object reference not set to an instance of an object. error in rowfilter line

Answer 1

Within your ds1 there is no table *reports.renewal_contact_t*. Change it to

cmd = New OracleCommand("select  PHONE from  reports.renewal_contact_t where run_date=to_date('" + TextBox1.Text + "','mm/dd/yyyy') and  EXP_DATE =to_date('" + TextBox2.Text + "','mm/dd/yyyy') and  region not in('TNP')", cn)
ada = New OracleDataAdapter(cmd)
ada.Fill(ds, "reports.renewal_contact_t")
' no need for a new dataset - as you fill ds (and not ds1)!!
ds.Tables("reports.renewal_contact_t").DefaultView.RowFilter = "PHONE NOT like'0'"

Answer 2

This will work against a dataset with a 'schema' similar to

**data example>*

Id   Value

1    303-888-8888
2    0-418-895-9598

TryCast(filteredDS.Tables(0).Rows.Cast(Of DataRow).Where(Function(row) Not row.ItemArray(1).ToString().Substring(0, 1).Equals("0")), IEnumerable(Of DataRow)).ToList().ForEach(Sub(row) row.Delete())

--removes any record where the phone starts with anything other than a zero