In SAP BW, what is the term for pre configuring number ranges for technical IDs such as SIDs and dimension IDs to improve performance?

Introduction / Context:
SAP BW uses various technical IDs, such as SIDs (surrogate IDs), dimension IDs, and fact table keys, to link master data and transactional data efficiently. Generating these IDs one by one with a database call for each new value would be inefficient. To improve performance, SAP employs number range buffering, which reserves blocks of numbers in memory so that IDs can be assigned quickly without constant trips to the database. Understanding this concept is useful for performance tuning and for answering certification questions.

Given Data / Assumptions:

• Technical IDs like SIDs and dimension IDs are needed when new master data values or dimension combinations are created.
• Each new ID normally requires a number from a number range object in the database.
• Repeated database access for every single ID can slow down data loads.
• The system provides mechanisms to buffer number ranges in memory.

Concept / Approach:
Number range buffering works by reserving a block of numbers from the database and storing them temporarily in application server memory. When a new SID or dimension ID is required, the system pulls the next number from the buffered range without needing an immediate round trip to the database. Once the buffered range is exhausted, another block is requested. This approach significantly reduces database overhead during large data loads and is transparent to end users and most administrators.

Step-by-Step Solution:
Step 1: Recognise that the main goal is to generate large quantities of technical IDs efficiently. Step 2: Understand that obtaining each ID one by one from the database would be slow and consume resources. Step 3: Recall that SAP uses buffering of number ranges to reserve a set of ID values in memory, which speeds up the allocation of new IDs. Step 4: Review the answer options and select the one that explicitly describes reserving ranges of technical IDs in advance to reduce database access. Step 5: Choose option c as the correct answer.

Verification / Alternative check:
In a high volume data load scenario, such as loading millions of new customer records into BW, each customer may require a new SID and possibly new dimension IDs. Without buffering, the system would execute a database call for each new ID. With number range buffering, the system requests, for example, a block of several thousand IDs at once. As records are processed, IDs are assigned from this block locally on the application server. Only after all buffered numbers are used is another block requested. Observed performance improvements in real projects confirm that this mechanism is effective and is correctly described as number range buffering.

Why Other Options Are Wrong:
Option a uses the term caching but inaccurately states that IDs are stored permanently in memory; number range buffering involves temporary blocks, not permanent storage. Option b mentions blobbing, a term normally associated with binary large objects, which is not relevant to technical ID generation. Option d refers to indexing, which optimises lookups but does not pre configure ID ranges. Option e describes partitioning, which is about splitting tables into segments, not about pre allocating ID values.

Common Pitfalls:
A common misunderstanding is to treat number range buffering as a form of long term caching or to confuse it with database indexing. Another pitfall is ignoring its impact on distributed systems; in multi server environments, buffer settings must be planned carefully to avoid gaps in ID sequences. For exam purposes, focus on the clear idea that pre configuring ranges of technical IDs for faster assignment is called number range buffering.

Final Answer:
Pre configuring ranges of technical IDs such as SIDs and dimension IDs for performance is called number range buffering, because ranges of technical IDs are reserved in advance to reduce database access during ID generation.