The
CurrentProject.Connection property was introduced in Microsoft Access 2000. It allows
developers who are writing ADO code in Microsoft Access to share the same ADO
connection that is used by Microsoft Access for the currently open database
(Jet or SQL Server database). This keeps developers from having to open and
manage separate ADO connections when they need to manipulate the database that
is currently open in Microsoft Access.
The
CurrentProject.AccessConnection property was introduced in Microsoft Access 2002. Like the
CurrentProject.Connection property, it allows developers to share an ADO connection with
Microsoft Access. The difference between these properties depends on whether
you are using an Access project (that is, a SQL Server database, ADP) or a Jet
database (MDB) file in Microsoft Access.
Access Projects (ADPs)
When you are using an Access project (ADP) in Microsoft Access
2002 or later, there is no difference between the
CurrentProject.Connection and the
CurrentProject.AccessConnection properties. Both properties return an ADO connection that uses
the SQL Server OLEDB provider (SQLOLEDB) as the data provider and the Microsoft
Access 10 OLEDB provider (Microsoft.Access.OLEDB.10.0) as a service
provider.
NOTE: The Microsoft Access 10 OLEDB provider is an OLEDB service
provider that was written specifically for use in Microsoft Access. It was not
designed to be used in applications other than Microsoft Access, and it is
unsupported in other applications.
Here is a typical connection
string that is returned by either property for an ADP that is connected to a
SQL Server database:
Provider=Microsoft.Access.OLEDB.10.0;Persist Security Info=True;Data Source=MySQLServer;User ID=<username>;Password=<strong password>";Initial Catalog=NorthwindCS;Data Provider=SQLOLEDB.1
Jet Databases (MDBs)
When you are using a Jet database in Microsoft Access 2002 or
later, the
CurrentProject.Connection and
CurrentProject.AccessConnection properties return different ADO connections. You can use either
property when you are writing ADO code in a Jet database. However, there are
certain situations where each property is useful. What follows is a breakdown
of what each property returns in Microsoft Access 2002 or later, and what you
should consider before using these properties.
CurrentProject.Connection
The
CurrentProject.Connection property behaves exactly as it did in Microsoft Access 2000. It
returns an ADO connection using the Microsoft Jet OLEDB provider
(Microsoft.Jet.OLEDB.4.0 provider). For example, here is a typical connection
string that is returned for a Jet database that is using the
CurrentProject.Connection property:
Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Program Files\Microsoft Office\Office10\Samples\Northwind.mdb
There are several scenarios where you should use
CurrentProject.Connection. If your application requires any of the following features, you
should use
CurrentProject.Connection to return the ADO connection.
- Jet and Replication Objects (JRO) code.
- Microsoft ADO Extensibility for DDL and Security (ADOX)
code.
- ADO code that requires Index support for ADO recordsets,
such as the Seek method.
The Microsoft Access 10 OLEDB provider does not fully support
the required OLEDB interfaces necessary for these features to work. If your
application requires these features, you must use a connection created with the
Jet OLEDB provider, which is returned by the
CurrentProject.Connection property.
CurrentProject.AccessConnection
The
CurrentProject.AccessConnection property will return an ADO connection that uses two OLEDB
providers. It uses the Jet OLEDB provider (Microsoft.Jet.OLEDB.4.0) as the data
provider and the new Microsoft Access 10 OLEDB provider
(Microsoft.Access.OLEDB.10.0) as a service provider. For example, here is a
typical connection string that is returned for a Jet database that is using the
CurrentProject.Connection property:
Provider=Microsoft.Access.OLEDB.10.0;Data Source=C:\Program Files\Microsoft Office\Office10\Samples\Northwind.mdb;User ID=Admin;Data Provider=Microsoft.Jet.OLEDB.4.0
There is one main advantage for using the
CurrentProject.AccessConnection property. Microsoft recommends you use
CurrentProject.AccessConnection if you intend to create ADO recordsets that will be bound to
Access forms. This is because the form will not be updateable unless it is
created using the Microsoft Access 10 OLEDB provider, even if the recordset is
updateable in ADO.