In ABAP programming, what are typical advantages and disadvantages of using database views defined in the Data Dictionary?

Introduction / Context:
In the SAP ABAP Data Dictionary, views are logical definitions that combine data from one or more tables. ABAP developers use views to simplify complex joins, restrict fields, or provide alternative representations of data. This question evaluates whether you understand both the benefits and the limitations of views in ABAP programming, especially when they are used in SELECT statements.

Given Data / Assumptions:

• Views are defined in the ABAP Data Dictionary (for example, database views, projection views, and maintenance views).
• Views do not store data physically; they are based on underlying tables or other views.
• ABAP programs can select from views just like from tables.
• The question asks for both advantages and disadvantages.

Concept / Approach:
The main advantage of views is abstraction. A view can hide complex joins and filters behind a single object name, making ABAP code easier to read and maintain. Views can also help enforce security and consistency by exposing only selected fields or records. However, because views are resolved by the database at query time, they can add performance overhead if the underlying join is complex or if the view is used inappropriately in high volume queries. Views also do not store data; they simply present data from base tables, so they cannot replace physical tables when persistence is required.

Step-by-Step Solution:
Step 1: Identify the main benefit of views, which is simplified and standardized access to related data across multiple tables. Step 2: Recall that views are logical and do not create new physical storage in the database. Step 3: Recognize that complex views can sometimes slow down queries because the database must resolve joins at runtime. Step 4: Choose the option that clearly mentions both easier data access and potential performance impact, while confirming that views do not store data themselves.

Verification / Alternative check:
You can verify by thinking of a simple join between a header table and an item table. Without a view, every ABAP program must write the same JOIN clause. With a database view, the join is defined once in the Data Dictionary and reused. This is more maintainable but may not change the underlying database cost; in some cases a poorly designed view can lead to slow queries. Also, when you insert or update data, you still write to base tables, not to most view types, which confirms that they do not store data physically.

Why Other Options Are Wrong:
Option B is wrong because views do not always improve performance and do not normally store join results as permanent data. Option C is incorrect because views can be used in SELECT statements in ABAP just like tables. Option D is wrong since views do not change physical table structures at runtime. Option E is incorrect because keys and relationships are defined on tables, not exclusively through views.

Common Pitfalls:
A common mistake is to believe that views are materialized by default and thus always faster; in SAP systems, database views are usually virtual. Another pitfall is using complex views in performance critical code without checking their execution plan. Developers should understand the underlying tables and indexes and use views where they provide clarity and security, not as a substitute for good data model design.

Final Answer:
Views simplify data access and improve readability by joining related tables logically, but they can introduce performance overhead and cannot store data themselves