OpenConnection Method

Applies To   DBEngine object, Workspace object.

Description

Opens a Connection object on an ODBC data source (ODBCDirect workspaces only).

Syntax

Set connection = workspace.OpenConnection(name, options, readonly, connect)

The OpenConnection method syntax has these parts.

Part

Description

connection

A Connection object variable to which the new connection will be assigned.

workspace

Optional. A variable of a Workspace object data type that references the existing Workspace object that will contain the new connection.

name

A string expression. See the discussion under Remarks.

options

Optional. A Variant that sets various options for the connection, as specified in Settings. Based on this value, the ODBC driver manager prompts the user for connection information such as data source name (DSN), user name, and password.

readonly

Optional. A Boolean value that is True if the connection is to be opened for read-only access and False if the connection is to be opened for read/write access (default).

connect

Optional. An ODBC connect string. See the Connect property for the specific elements and syntax of this string. A prepended "ODBC;" is required. If connect is omitted, the UID and/or PWD will be taken from the UserName and Password properties of the Workspace.


Settings

The options argument determines if and when to prompt the user to establish the connection, and whether or not to open the connection asynchronously. You can use one of the following constants.

Constant

Description

dbDriverNoPrompt

The ODBC Driver Manager uses the connection string provided in dbname and connect. If you don't provide sufficient information, a run-time error occurs.

dbDriverPrompt

The ODBC Driver Manager displays the ODBC Data Sources dialog box, which displays any relevant information supplied in dbname or connect. The connection string is made up of the DSN that the user selects via the dialog boxes, or, if the user doesn't specify a DSN, the default DSN is used.

dbDriverComplete

Default. If the connect argument includes all the necessary information to complete a connection, the ODBC Driver Manager uses the string in connect. Otherwise it behaves as it does when you specify dbDriverPrompt.

dbDriverCompleteRequired

This option behaves like dbDriverComplete except the ODBC driver disables the prompts for any information not required to complete the connection.

dbRunAsync

Execute the method asynchronously. This constant may be used with any of the other options constants.


Remarks   Use the OpenConnection method to establish a connection to an ODBC data source from an ODBCDirect workspace. The OpenConnection method is similar but not equivalent to OpenDatabase. The main difference is that OpenConnection is available only in an ODBCDirect workspace.

If you specify a registered ODBC data source name (DSN) in the connect argument, then the name argument can be any valid string, and will also provide the Name property for the Connection object. If a valid DSN is not included in the connect argument, then name must refer to a valid ODBC DSN, which will also be the Name property. If neither name nor connect contains a valid DSN, the ODBC driver manager can be set (via the options argument) to prompt the user for the required connection information. The DSN supplied through the prompt then provides the Name property.

OpenConnection returns a Connection object which contains information about the connection. The Connection object is similar to a Database object. The principal difference is that a Database object usually represents a database, although it can be used to represent a connection to an ODBC data source from a Microsoft Jet workspace.

See Also   Cancel method, Connection object, StillExecuting property.

Example

This example uses the OpenConnection method with different parameters to open three different Connection objects.

Sub OpenConnectionX()

    Dim wrkODBC As Workspace
    Dim conPubs As Connection
    Dim conPubs2 As Connection
    Dim conPubs3 As Connection
    Dim conLoop As Connection

    ' Create ODBCDirect Workspace object.
    Set wrkODBC = CreateWorkspace("NewODBCWorkspace", _
        "admin", "", dbUseODBC)

    ' Open Connection object using supplied information in
    ' the connect string. If this information were
    ' insufficient, you could trap for an error rather than
    ' go to an ODBC Driver Manager dialog box.
    MsgBox "Opening Connection1..."
    Set conPubs = wrkODBC.OpenConnection("Connection1", _
        dbDriverNoPrompt, , _
        "ODBC;DATABASE=pubs;UID=sa;PWD=;DSN=Publishers")

    ' Open read-only Connection object based on information
    ' you enter in the ODBC Driver Manager dialog box.
    MsgBox "Opening Connection2..."
    Set conPubs2 = wrkODBC.OpenConnection("Connection2", _
        dbDriverPrompt, True, "ODBC;DSN=Publishers;")

    ' Open read-only Connection object by entering only the
    ' missing information in the ODBC Driver Manager dialog
    ' box.
    MsgBox "Opening Connection3..."
    Set conPubs3 = wrkODBC.OpenConnection("Connection3", _
        dbDriverCompleteRequired, True, _
        "ODBC;DATABASE=pubs;DSN=Publishers;")

    ' Enumerate the Connections collection.
    For Each conLoop In wrkODBC.Connections
        Debug.Print "Connection properties for " & _
            conLoop.Name & ":"

        With conLoop
            ' Print property values by explicitly calling each
            ' Property object; the Connection object does not
            ' support a Properties collection.
            Debug.Print "    Connect = " & .Connect
            ' Property actually returns a Database object.
            Debug.Print "    Database[.Name] = " & _
                .Database.Name
            Debug.Print "    Name = " & .Name
            Debug.Print "    QueryTimeout = " & .QueryTimeout
            Debug.Print "    RecordsAffected = " & _
                .RecordsAffected
            Debug.Print "    StillExecuting = " & _
                .StillExecuting
            Debug.Print "    Transactions = " & .Transactions
            Debug.Print "    Updatable = " & .Updatable
        End With

    Next conLoop

    conPubs.Close
    conPubs2.Close
    conPubs3.Close
    wrkODBC.Close

End Sub