Update Error in Visual Basic 2010 - database

Question

Im getting a Data type mismatch in criteria expression.
This is an update button Im trying to implement.
Access_Num is the only number(data_type) here.
I'm using MSACCESS2007
Is it a good pracrice to make all data types in the database as text?
Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
cn = New OleDbConnection(con)
cn.Open()
With cmd
.Connection = cn
.CommandText = "Update [Book] SET [Book_ID] = '" & TextBox1.Text & _
"', [Access_Num] = '" &Integer.Parse(TextBox2.Text) & _
"', [Title] = '" & TextBox3.Text & _
"', [Author] = '" & TextBox4.Text & _
"', [Publisher] = '" & TextBox5.Text & _
"', [Category] = '" & ComboBox1.Text & _
"', [Contents] = '" & TextBox7.Text & _
"', [Availability] = '" & ComboBox2.Text & "' WHERE [Access_Num] = '" & Integer.Parse(TextBox2.Text) & "'"
.ExecuteNonQuery()
End With
Try
cmd.ExecuteNonQuery()
cmd.Dispose()
cn.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
'cn.Close()
'cmd.Dispose()
MsgBox("Successfully Updated")
End Sub

Answer 1

Your problem is that you have string delimiters everywhere. Remove them for all fields that aren't strings:
With cmd
.Connection = cn
.CommandText = "Update [Book] SET [Book_ID] = '" & TextBox1.Text & _
"', [Access_Num] = " & Integer.Parse(TextBox2.Text) & _
", [Title] = '" & TextBox3.Text & _
"', [Author] = '" & TextBox4.Text & _
"', [Publisher] = '" & TextBox5.Text & _
"', [Category] = '" & ComboBox1.Text & _
"', [Contents] = '" & TextBox7.Text & _
"', [Availability] = '" & ComboBox2.Text & "' WHERE [Access_Num] = " & Integer.Parse(TextBox2.Text)
.ExecuteNonQuery()
End With
Note that a better way would be to use parameters for the query, since that also avoids SQL injection.
Is it a good pracrice to make all data types in the database as text?
No, certainly not! That's an awful practice. Data types should represent the data stored in the column, and be the smallest practical type to represent that data.