Buffer Concept (BW-BPS) 

Use

Planning methods work with data that is stored in a buffer. This is called the planning buffer. Data can be divided into:

·        Transaction data (plan data)

·        Master data, metadata (Customizing objects)

All changes to the data are written to the planning buffer. Therefore you do not have to save continually. Furthermore, performance is improved.

However, what data is written to the buffer is dependent on the data selections made in the planning package and in the detail applications (for example, the planning functions).

Detail applications are all elements that can be executed and are displayed in the right-hand screen in the planning environment; these include, for example, the planning definition screens or a planning function.

Each user writes data to a personal planning buffer. A user’s data in their (personal) planning buffer is locked against changes by other users.

Activities

Every time a detail application is executed, the system first checks whether the requested data already exists in the planning buffer. If it does, the system accesses the version of data available in the planning buffer. If the data is not already in the buffer, the system reads it either from:

·        The database table (Customizing objects), or

·        The InfoCube (plan data)

and writes it to the planning buffer.

Commit Event

When you exit a detail application, the system writes the corresponding data to the planning buffer.

You get to a manual planning layout and execute a planning function. In the system, the following happens:

§         ...

                                                  i.       The system writes the modified transaction data to the planning buffer.

                                                ii.       The planning function refers to the planning buffer data; it modifies the data and writes it back to the planning buffer.

                                               iii.       Manual planning reads the modified data from the planning buffer and displays it on the screen.

You can only exit a detail application when all of the data you have entered is consistent; that is, when your entries enable the detail application to be executed correctly. If necessary, you have to terminate the detail application. A termination only ends the current detail application and only causes the data from this detail application to be deleted in the buffer. All data for previous detail applications is still buffered. 

Saving

You can save at any point. The data is then written to the InfoCube or the database table and also remains in the buffer. The buffered data is only deleted when you exit the planning application.

As the data is still in the planning buffer, locks that are set automatically remain set.

Therefore, BW-BPS never changes the data in a transactional InfoCube directly, but instead returns a delta. Delta records are transformed when they are transferred to the planning buffer. The planning buffer retains delta records as it does all other data records.

You can save data in two ways:

·        Save All

Saves master data, metadata and transaction data. Data (or delta) is written from the planning buffer back to the database tables and the InfoCube.

·        Save Model

Only saves master data and metadata. Data is written from the planning buffer back to the database tables.