Deleting Tables

:confused:
I am Developing a simple VBA program for Access for my final year of my Degree and I have come up with a problem that I don’t seem to be able to fix.

I have create tables using SQL

SQL = "CREATE TABLE tblInvoiceLines" & _
"(InvoiceNo LONG, PartNo LONG," & _
"Quantity LONG)"

DoCmd.RunSQL (SQL)


Deleting this with the below code works,

SQL = ""
'This will delete the Invoice Line Table
SQL = "DROP TABLE tblInvoiceLines"
DoCmd.RunSQL (SQL)


But once I alter the table with the below code the Delete command doesn’t work, does anyone know how I can fix this problem?

SQL = "ALTER TABLE tblInvoiceLines " & _
"ADD CONSTRAINT fkInvoiceNo " & _
"FOREIGN KEY NO INDEX (InvoiceNo) REFERENCES " & _
"tblInvoices (InvoiceNo) " & _
"ON UPDATE CASCADE " & _
"ON DELETE CASCADE "


conDatabase.Execute SQL


Thanks
Coops