Introduction To Database Questions and Answers

Answer: A

Correct answer: True

XML matters in database processing as the standard way of moving structured data between systems that share no common database: web services, business-to-business exchange, configuration and document storage. Most DBMS products now store and query XML directly, and the family of related standards - XPath, XSLT, XML Schema - goes with it.

Answer: D

Correct answer: Database Administrator

DBA stands for Database Administrator - the person responsible for a database’s structure, security, backup and recovery, performance and users. The role is distinct from that of the developers who write the applications above it.

Answer: C

Correct answer: All of these

Oracle, FoxPro and Access are all database management systems - enterprise, legacy PC and desktop respectively. They differ in scale and capability, not in kind.

Answer: D

Correct answer: All of the above

A view gives all three. Security: users can be granted access to the view and not to the underlying table, so they see only certain rows or columns. Derived columns: a view can compute values that are not stored. Simplicity: a complex join can be defined once and then queried as though it were a single table.

Answer: B

Correct answer: False

Data is stored in tables (relations), which have rows and columns. A spreadsheet also has rows and columns, but that resemblance is superficial: a table has a defined structure, typed columns, keys, and relationships to other tables, and is managed by a DBMS that enforces all of it.

Answer: B

Correct answer: Stringent real-time requirements

A DBMS adds layers - query processing, locking, logging - and with them latency that is hard to bound. Where an application must guarantee a response within a few microseconds, direct file access is more predictable. The other two options are arguments for a DBMS, not against: concurrent access and complex relationships are exactly what it exists to manage.

Answer: A

Correct answer: IDMS

IDMS implemented the CODASYL DBTG network model, the dominant pre-relational approach, in which records are linked by explicit sets and navigated pointer by pointer. It is still in use on mainframes. DB2 is relational; dBase-II and R:base were PC products.

Answer: B

Correct answer: False

The one ranked hardest to use is Oracle, not SQL Server. SQL Server sits between Access and Oracle: an enterprise product, but a more approachable one to administer.