OpenConnection Method (DAO)

Microsoft DAO 3.60

OpenConnection Method

           

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.