It depends on the data provider. See: ConnectionString.com And, perhaps more specifically: The .NET Data Provider for Oracle . The connection string should look very similar in your web.config file. The only differences are likely to be the system name / db, user id, pwd, etc.
Namespaces :
you need to know which type of objects can have the same name and which do not. To do this, you need to introduce the concept of a namespace. A namespace defines a group of object types within which all names must be uniquely identified by a schema and name. Objects in different namespaces have the same name.
Here is also a good tutorial that you can track that is specific to ASP.NET. And another article that might be of interest.
And a piece of code (using the Oracle .NET provider :)
public DataTable myDataTable(string SQL, string ConnStr) { OracleConnection cn = default(OracleConnection); DataSet dsTemp = null; OracleDataAdapter dsCmd = default(OracleDataAdapter); cn = new OracleConnection(ConnStr); cn.Open(); dsCmd = new OracleDataAdapter(SQL, cn); dsTemp = new DataSet(); dsCmd.Fill(dsTemp, "myQuery"); cn.Close(); return dsTemp.Tables[0]; }