OleDbCommand.ExecuteNonQuery() does not save changes in ms access database

Question

I have .mdb database, and code like this:

using (OleDbConnection connection = new OleDbConnection(myConnectionString))
{
    using (OleDbCommand         


        

Answer 1

When we we add .mdb in project root in VS ,when change structure ,VS default delete .mdb file in debug folder and replace new file; now you can change this defult :

1- right click .mdb file and select option

2- set Copy To Output Directory to Do Not Copy