CDataConnection Class

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06/05/2017

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Manages the connection with the data source.

Syntax

class CDataConnection

Members

Methods

CDataConnection	Constructor. Instantiates and initializes a `CDataConnection` object.
Copy	Creates a copy of an existing data connection.
Open	Opens a connection to a data source using an initialization string.
OpenNewSession	Opens a new session on the current connection.

Operators

operator BOOL	Determines whether the current session is open or not.
operator bool	Determines whether the current session is open or not.
operator CDataSource&	Returns a reference to the contained `CDataSource` object.
operator CDataSource*	Returns a pointer to the contained `CDataSource` object.
operator CSession&	Returns a reference to the contained `CSession` object.
operator CSession*	Returns a pointer to the contained `CSession` object.

Remarks

CDataConnection is a useful class for creating clients because it encapsulates necessary objects (data source and session) and some of the work you need to do when connecting to a data source

Without CDataConnection, you have to create a CDataSource object, call its OpenFromInitializationString method, then create an instance of a CSession object, call its Open method, then create a CCommand object and call its Open* methods.

With CDataConnection, you only need to create a connection object, pass it an initialization string, then use that connection to open commands. If you plan on using your connection to the database repeatedly, it is a good idea to keep the connection open, and CDataConnection provides a convenient way to do that.

Note

If you are creating a database application that needs to handle multiple sessions, you will need to use OpenNewSession.

Requirements

Header: atldbcli.h

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