Question

I’m writing small VB.Net app which should build reports based on data gathered from some external MDB-files (Access 2007). It was planned that this app will use parametrized SQL queries to collect data. One of the parameters for these queries is path to the external MDB-file.

Here goes sample code:

Dim conn As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;" _
                                & "Data Source=C:\Temp\Temp.mdb;")
conn.Open()

Dim cmd As New OleDbCommand()
cmd.Connection = conn
cmd.CommandType = CommandType.Text
cmd.CommandText = "SELECT * INTO Trend FROM TI IN '?' WHERE TI.Id=?;"
With cmd.Parameters
    .Add("@p1", OleDbType.VarChar).Value = "C:\Temp\Source.mdb"
    .Add("@p2", OleDbType.Integer).Value = 5
End With

cmd.ExecuteNonQuery()
conn.Close()

Looks simple but it doesn’t works. After launch my app throws following exception – System.Data.OleDb.OleDbException: Disk or network error.

Have spent a whole day to make it work with no success. What have I done wrong?

Answer 1

This is a comment that others have suggested is the answer to the question:

Nothing in an Access/Jet/ACE FROM clause is parameterizable (unless it’s inside a subquery, of course).

With Access/Jet/ACE your only choice is to use some other method to write the FROM clause on-the-fly.