Question Bank

FILL IN THE BLANKS

1. _______________ contains the structure of database.
2. ______________is a hierarchical database system.
3. ______________is used to specify database retrievals and updates.
4. Middle level managers use ___________ information.
5. __________ is an organized collection of facts.
6. The smallest piece of meaningful information in a file is called_______________.
7. _____________ is responsible for physical design and maintenance of database.
8. Hierarchical network and relational data models are___________data models.
9. Data on a last level of a database tree is called___________________
10. ___________ is a collection of entries where each entry corresponds to a data record.
11. In the relational data model the columns of a table are called_________________.
12. A_______________is a mechanism that provides abstraction for database application.
13. The _______ model is based on the mathematical concept of a relation.
14. A relationship is always established between_____________.
15. Relational tables show only______________ relationship.
16. The values for an attribute are drawn from a set of values known as___________.
17. Relational model of data management is based on______________.
18. In the relational database model, the columns of a table are called___________.
19. In a relational database_______________ are not allowed to have null values.
20. The primary key of a relation is a minimal_____________.
21. In a relational database a referential integrity constraint is specified with the help of____________________.
22. Data about data is normally termed as_______________.
23. The primary key index does not allow ________________ data in a field.
24. If an entity X is existence-dependent on entity Y, then X is said to be__________.
25. A ___________ user is the owner of an Oracle’s dictionary tables.
26. GRANT is a________________ command.
27. The command ROLLBACK TO SAVEPOINT is used to _______________rollback a transaction.
28. The list of tuples selected using the SQL SELECT FROM command may contain_______________entries.
29. Along with the GROUP BY clause, one can use the__________________clause to define a condition on the group of tuples associated with each value of the grouping attributes.
30. A view of the database that appears to an application program is known as_____________.
31. When one column of a table refers to the values in another column of the same table, it introduces a___________integrity constraint.
32. The universal quantifier in relational calculus can be implemented using_____________ SQL command.
33. _________________ Symbol in SQL indicates that all attributes of the relation are to be retrieved.
34. A______________is an operation on a relation A producing a relation B which contains only selected attributes of A.
35. The embedded sql SELECT command cannot reference relations into which tuples are being_______________.
36. An ________________API is common for all types of relational databases.
37. The statement “An ODBC transaction can be nested” is________________.
38. SQL based RDBMS queries collect tuples having same values of attributes in the _______________clause in one cluster.
39. A functional dependency is relationship between___________________.
40. _______________is a status variable.
41. User defined cursors are called________________cursors.
42. Variables used for communicating with the database systems are called_____________variables.
43. The program in which the SQL is embedded is known as the ___________program.
44. Every embedded SQL statements begin with___________command.
45. _____________is a mechanism which allows a programmer to process the result of a query, one tuple at a time.
46. A multilevel index leads to a___________________.
47. When a table has no repeating groups, it is said to be in________________.
48. The various kinds of data describe an entity, known as its_______________.
49. A___________is always established between two entities.
50. If relation is in _______________,it is in 3NF also.
TRUE OR FALSE

1. A weak entity set has a primary key.
2. Every weak entity set can be converted into a strong entity set by adding appropriate attributes.
3. In a B-tree non-leaf nodes are smaller than the leaf nodes.
4. Boyce-Codd Normal Form is also in Third normal form.
5. Aggregation operation is used to construct complex entities.
6. An E-R model uses doubly outlined rectangle to represent weak entity set.
7. Codd gave 12 rules for any RDBMS to be accepted as a full fledged RDBMS.
8. In a lock-based schedule deadlocks cannot occur.
9. Isolation is a desired property of a transaction.
10. Insertion of data into a B-tree may cause nodes to split.
11. Multiple hashing is a method for collision-resolution.
12. IDMS is an example of network database.
13. Deadlocks can be described precisely in terms of a directed graph.
14. The cost of processing a query is not dependent on disk access.
15. If a write lock is applied to a data item then any number of transaction can read it but no transactions can update it.
16. Order in which statements belonging to different transactions, is executed, is called a schedule.
17. Every two-phase schedule can be produced by a time stamp ordered scheduler.
18. A deadlock exists in the system if and only if the wait for graph does not contain a cycle.
19. An indexed sequential file is not suitable for applications which require batch access.
20. All data values are not atomic.
21. An ODBC transaction can span multiple databases.
22. A database of a particular DBMS on some given machine can serve as an ODBC data source if it is known to the ODBC driver manager
23. + and – are mathematical as well as string operators.
24. Details regarding the users of the data are included in the data dictionary.
25. API is a function used to call the operating system.
26. In a nested SQL query, the result of the inner query is passed to the outer query.
27. Null value means string of characters.
28. Foreign key value should not be left blank.
29. NULL value means absence of data.
30. DROP VIEW command is used to dispose a view not needed anymore.
31. NOT IN is not functional in SQL.
32. Check box is associated with logical type of data.
33. To eliminate duplicate tuples from the result of SQL query key word UNIQUE is used.
34. Domain integrity can be enforced using check clause in create table command in ORACLE.
35. Only two files can be linked for a single SET RELATION command.
36. JOIN creates a new database file by joining two or more database files.
37. The functional dependencies X->Y and YZ->W imply the functional dependency XZ->W.
38. In a relational database, the foreign key of a relation would be the primary key of an another relation.
39. A candidate key can be a subset of a super key.
40. Any equijoin can be expressed using natural join and renaming operators.
41. The conceptual level is a level of indirection.-(F)
42. The conceptual view is a view of the total database content.-(F)
43. System tables are catalog in relational system.-(T)
44. A base table is a table, which is a derived table.-(F)
45. The database schema and an instance of the database are the same thing.-(F)
46. Hierarchical data model uses the concept of SET.-(F)
47. Relational data model provides better data independence than network model.-(T)
48. User’s view is also called external view.-(T)
49. Physical data models are used to describe data at the highest level.-(F)
50. A relationship is an association among several entities.-(T)

SHORT QUESTIONS

1. What is mean by metadata?
2. List four significant differences between a file processing system and a DBMS?
3. What are the five major functions of a database administrator?
4. What are the different types of database end users?
5. Discuss the actions that should be performed by a DBMS?
6. What is mean by data independence?
7. Differentiate between privacy, security, correctness and integrity of a database?
8. List some of the disadvantages of using a DBMS?
9. What is mean by query processor?
10. What is DML? What are the two types of DML?
11. Explain the difference between physical and logical data independence?
12. What are the drawbacks of relational DBMS?
13. What is mean by specialization?
14. What is mean by data manager?
15. What is mean by nested queries?
16. Define External view?
17. Discuss the main categories of data model?
18. What is referential integrity?
19. Explain any five Codd’s rules?
20. What do you mean by base and derived relation?
21. Explain natural join with example?
22. Explain 3rd Normal Form (3NF) with an example?
23. Define partial dependency?
24. Why do recovery routines use a log?
25. What is a statistical database?
26. What is a phantom deadlock?
27. How can we avoid deadlock?
28. What do you understand by the term concurrency?
29. What is mean by generalization?
30. What is mean by aggregation?
ESSAY

1. Explain the distinction between the representation of association and relationship in the network and hierarchical models?
2. Compare relational network and hierarchical data models?
3. Explain different aggregate functions?
4. What are the advantages and disadvantages of relational data model as compared to other traditional data models?
5. Explain the transaction process in sql?
6. Describe the three-schema architecture?
7. Explain the following keys with examples
(a)Primary key
(b)Candidate key
(c)Foreign key
8. Explain operations of relational algebra along with their syntaxes?
9. What are the criteria which determine whether base table updations are possible through views or not?
10. Explain different SQL standards?
11. Explain the following relationships with examples
(a) One to one
(b) One to many
(c) Many to many
9. Explain the 3-level architecture of a DBMS as per the ANSI/SPARC model?
10. Define Normalization? Why normalization is carried out?
11. Who is DBA? Explain the role of DBA in an organization?
12. Define sequential files? What are the advantages and disadvantages of sequential files?
13 What are advantages of OODBMS over RDBMS?
14 Explain how concurrency can lead to inconsistency?
15 Explain the concept of two phase locking and explain how it guarantees serialisability?
16 What are desired features of a good hashing algorithm?
17 Explain the different type of joins?
18 Explain different integrity constraints?