Which of the following will occur when a view is created on a DB2 table?
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Memory usage is reduced
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Query compilation time is reduced
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Data access time is increased
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Data access control is increased
Views are virtual tables that enhance data security and access control by limiting what data users can see or modify. By creating a view on a table, administrators can grant users access only to specific rows or columns, effectively increasing control over data access. Views do not reduce memory usage (they store no data), do not reduce compilation time (queries are still compiled), and do not increase data access time (access is similar to the base table).
Creating a view over a DB2 table increases data access control — correct, and this is the classic reason views are used. A view lets you expose only certain columns or rows (via WHERE clauses) of underlying tables to a set of users, letting you grant access to the view instead of the base table, effectively restricting what data a user can see/manipulate — that's an access-control/security benefit, not a performance one. Views don't reduce memory usage or query compilation time (the view's defining query still has to be parsed/optimized, often adding overhead by merging into the outer query), and they don't inherently increase data access time either — those options describe performance characteristics unrelated to what views are actually for.