Extending MDX with Stored Procedures - Microsoft SQL Server 2008 Analysis Services - page 254

Database Developer
writes custom code in
procedural language
SessionOpenedEvent

Managed Stored
Procedure is deployed
to Analysis Server

Analysis Services User creates

a session

(if UserA)
Create Member A
(if UserB)
Create Member B
Else

SessionOpenedEvent
(if UserA)
Create Member A
(if UserB)
Create Member B
Else

Create Member C

Create Member C

FIGURE 14.9 Process to create a stored procedure with a callback.

In Analysis Services 2008, stored procedures can subscribe to the four events shown in
Table 14.6. Your code can subscribe to events using mechanism of events and delegates
provided by .NET Framework.

TABLE 14.6

Callback Plug-In Events

Name Description Demand

A new user session is
created on the server.

SessionOpened Context.Server.SessionOpened

User's session is
about to be closed.

SessionClosing Context.Server.SessionClosing

First time a cube is
queried by a session.

CubeOpened Context.CurrentConnection.CubeOpened

No more queries will
be served for this
cube on the session.

CubeClosing Context.CurrentConnection.CubeClosing

To tell Analysis Services which class contains callbacks, you can use the custom attribute
[PluginAttribute] . Analysis Services 2008 extends the server object model interface with
new functions, which you can use to specify a callback function that the server calls on a
certain events. Listing 14.4 shows an example of a library that implements a personaliza-
tion plug-in.

LISTING 14.4

Stored Procedure That Implements a Plug-In

namespace PasTestPlugIn