VB.net sql table not showing last rows - sql

Question

What I am doing-
Importing 406 rows into 5 sql tables from excel sheet.
After import, I am manually saving data one by one into each of the 5
tables on button click event and displaying on datagridview..
After saving each record, I am refreshing datagridview.
My problem -
Records are getting saved properly, but datagridview shows only
408 records, where actual no. of records are 412.
When viewed from server explorer also, only 408 records are
shown.
But table properties show that there are 412 rows.
This problem is with only first table.
my code:-
cmd.CommandText = String.Empty
cmd.Parameters.Clear()
cmd.CommandText = "INSERT into pd([Adm No],[DOA],[Name],[Course],[Fees Due],[Concession],[Contact No 1]," & _
"[Contact No 2],[E-Mail],[Year of Passing],[Address],[DOB],[College])" & _
" values(#admno,#doa,#name,#course,#totalfees,#concession,#contactno1,#contactno2,#email,#yop," & _
"#address,#dob,#college)"
cmd.Parameters.AddWithValue("#admno", i.ToString)
cmd.Parameters.AddWithValue("#doa", date_format.format_date(doa.Value.Date))
cmd.Parameters.AddWithValue("#name", txt_name.Text)
cmd.Parameters.AddWithValue("#course", combo_course.SelectedItem.ToString)
cmd.Parameters.AddWithValue("#totalfees", txt_totalfees.Text)
cmd.Parameters.AddWithValue("#concession", txt_concession.Text)
cmd.Parameters.AddWithValue("#contactno1", txt_contact1.Text)
cmd.Parameters.AddWithValue("#contactno2", txt_contact2.Text)
cmd.Parameters.AddWithValue("#email", txt_email.Text)
cmd.Parameters.AddWithValue("#yop", txt_yop.Text)
cmd.Parameters.AddWithValue("#address", txt_address.Text)
cmd.Parameters.AddWithValue("#dob", date_format.format_date(dob.Value.Date))
cmd.Parameters.AddWithValue("#college", txt_college.Text)
If con.State = ConnectionState.Closed Then
con.Open()
End If
cmd.Connection = con
cmd.ExecuteNonQuery()
'save fees details
cmd.CommandText = String.Empty
cmd.Parameters.Clear()
cmd.CommandText = "INSERT into fees([Adm No],[Name],[Fees Due],[Fees Paid],[No of Installments]," & _
"[Installment Amounts],[Receipt Nos],[Dates of Transaction],[Mode],[Bank],[Due Date]" & _
",[Total Fees],[Concession],[Cheque No],[Course])" & _
" values(#admno,#name,#feesdue,#feespaid,#noi,#instamnt,#rcno,#dot,#mode,#bank,#dd," & _
"#total,#concession,#chqno,#course)"
cmd.Parameters.AddWithValue("#admno", i.ToString)
cmd.Parameters.AddWithValue("#name", txt_name.Text)
cmd.Parameters.AddWithValue("#feesdue", (CInt(txt_totalfees.Text) - CInt(txt_concession.Text)))
cmd.Parameters.AddWithValue("#feespaid", CInt(0))
cmd.Parameters.AddWithValue("#noi", CInt(0))
cmd.Parameters.AddWithValue("#instamnt", "")
cmd.Parameters.AddWithValue("#rcno", "")
cmd.Parameters.AddWithValue("#dot", "")
cmd.Parameters.AddWithValue("#mode", "")
cmd.Parameters.AddWithValue("#bank", "")
cmd.Parameters.AddWithValue("#dd", "")
cmd.Parameters.AddWithValue("#total", CInt(txt_totalfees.Text))
cmd.Parameters.AddWithValue("#concession", txt_concession.Text)
cmd.Parameters.AddWithValue("#chqno", "")
cmd.Parameters.AddWithValue("#course", combo_course.SelectedItem.ToString)
If con.State = ConnectionState.Closed Then
con.Open()
End If
cmd.Connection = con
cmd.ExecuteNonQuery()
'save photo
If Not PictureBox1.Image Is Nothing Then
cmd.CommandText = String.Empty
cmd.Parameters.Clear()
cmd.CommandText = "Insert into img values(#adm,#name,#imge)"
Dim para As New SqlCeParameter("imge", SqlDbType.Image)
Dim ms As New MemoryStream
PictureBox1.BackgroundImage.Save(ms, PictureBox1.BackgroundImage.RawFormat)
Dim data As Byte() = ms.GetBuffer
para.Value = data
cmd.Parameters.AddWithValue("#adm", lb_admno.Text)
cmd.Parameters.AddWithValue("#name", txt_name.Text)
cmd.Parameters.Add(para)
If con.State = ConnectionState.Closed Then
con.Open()
End If
cmd.Connection = con
cmd.ExecuteNonQuery()
Else
cmd.CommandText = String.Empty
cmd.Parameters.Clear()
cmd.CommandText = "Insert into img values(#adm,#name,#imge)"
Dim para As New SqlCeParameter("imge", SqlDbType.Image)
Dim ms As New MemoryStream
PictureBox1.BackgroundImage.Save(ms, PictureBox1.BackgroundImage.RawFormat)
Dim data As Byte() = ms.GetBuffer
para.Value = data
cmd.Parameters.AddWithValue("#adm", lb_admno.Text)
cmd.Parameters.AddWithValue("#name", txt_name.Text)
cmd.Parameters.Add(para)
If con.State = ConnectionState.Closed Then
con.Open()
End If
cmd.Connection = con
cmd.ExecuteNonQuery()
End If
cmd.CommandText = String.Empty
cmd.Parameters.Clear()
cmd.CommandText = "insert into attend values(#adm,#name,#course,#dt,#stat)"
cmd.Parameters.AddWithValue("#adm", lb_admno.Text)
cmd.Parameters.AddWithValue("#name", txt_name.Text)
cmd.Parameters.AddWithValue("#course", combo_course.SelectedItem.ToString)
cmd.Parameters.AddWithValue("#dt", "")
cmd.Parameters.AddWithValue("#stat", "")
If con.State = ConnectionState.Closed Then
con.Open()
End If
cmd.Connection = con
cmd.ExecuteNonQuery()
cmd.CommandText = String.Empty
cmd.Parameters.Clear()
cmd.CommandText = "insert into testdb values(#adm,#name,#course,#tname,#tdate,#marksob,#marksout)"
cmd.Parameters.AddWithValue("#adm", lb_admno.Text)
cmd.Parameters.AddWithValue("#name", txt_name.Text)
cmd.Parameters.AddWithValue("#course", combo_course.SelectedItem.ToString)
cmd.Parameters.AddWithValue("#tname", "")
cmd.Parameters.AddWithValue("#tdate", "")
cmd.Parameters.AddWithValue("#marksob", "")
cmd.Parameters.AddWithValue("#marksout", "")
If con.State = ConnectionState.Closed Then
con.Open()
End If
cmd.Connection = con
cmd.ExecuteNonQuery()

Answer 1

problem was in the code of importing records. I was reading cells of excel file and inserting them into five tables.
Problem arises only if I import records in all five tables one by one, but if I import records into only three tables then the problem doesn't arise.
This solved my problem, but I didn't happen to know the actual reason behind it. Why can't I import records into five tables one after another? If anyone finds the reason behind the error please comment.