Structured Query Language Quiz

Relational model and Normalization Quiz

1. In a CREATE TABLE statement, each column/attribute must have a data type associated with it. TRUE / FALSE?

TRUE
FALSE

2. Referential integrity ensures that a value stored in the foreign key attribute matches a primary key attribute in the referred table. TRUE/FALSE?

TRUE
FALSE

3. A view is part of the external schema and is considered as an acceptable way to offer simpler tables with customized attribute names to the user. TRUE/FALSE?

TRUE
FALSE

4. A view can be referred to like a table in a SELECT. TRUE/FALSE?

TRUE
FALSE

5. Besides a shorthand reference to the table throughout the query, using an alias makes the query run much faster as a result. TRUE/FALSE?

TRUE
FALSE

6. Deleting from a view that is based on a natural join of its base tables is acceptable. TRUE/FALSE?

TRUE
FALSE

7. If both NOT NULL and UNIQUE integrity constraints are defined on an attribute, the designation implies that the attribute is a candidate key. TRUE/FALSE?

TRUE
FALSE

8. An INSERT requires the input values sequence to match the attribute sequence when the attributes are specified in the INSERT statement. TRUE/FALSE?

TRUE
FALSE

9. The SQL SELECT statement includes the sequence of steps to exectue a query besides the operations that the server uses to answer the query. TRUE/FALSE?

TRUE
FALSE

10. Triggers provide a mechanism to monitor specific changes to a table and perform additional actions based on the altered data. TRUE/FALSE?

TRUE
FALSE

Score =

Correct answers:

Three levels in database system architecture quiz

Relational model and Normalization Quiz

1. The layout of the data within the disk file system is found at the logical/conceptual level. TRUE / FALSE?

TRUE
FALSE

2. There is exactly one schema at the conceptual level for a database. TRUE/FALSE?

TRUE
FALSE

3. There is exactly one schema at the external level of a database. TRUE/FALSE?

TRUE
FALSE

4. A user’s access to the database can be limited by the schema at the external level. TRUE/FALSE?

TRUE
FALSE

5. The indexing schemes for each table is found at the external level. TRUE/FALSE?

TRUE
FALSE

6. The mappings between the levels provides for program-data independence. TRUE/FALSE?

TRUE
FALSE

7. The mapping between the external and logical levels provides various views to the users. TRUE/FALSE?

TRUE
FALSE

8. The levels in the architecture in sequence is logical-external-physical. TRUE/FALSE?

TRUE
FALSE

9. A physical schema is typically derived from the logical schema. TRUE/FALSE?

TRUE
FALSE

10. An Entity-Relationship model will map most closely to the logical schema. TRUE/FALSE?

TRUE
FALSE

Score =

Correct answers:

Quiz on normalization and functional dependency 6

Relational model and Normalization Quiz

1. Functional dependency analysis helps in the normalization of a relational schema. TRUE / FALSE?

TRUE
FALSE

2. Normalization attempts to reduce redundant information that are stored as part of a relation. TRUE/FALSE?

TRUE
FALSE

3. Redundancy is at the root of insertion and deletion anomalies in a relational database. TRUE/FALSE?

TRUE
FALSE

4. A null value has exactly one interpretation, ie., one meaning. TRUE/FALSE?

TRUE
FALSE

5. A functional dependency is a relationship between an attribute "Y" and a determinant (1 or more other attributes) such that for a given value of a determinant the value of the attribute Y is uniquely defined. TRUE/FALSE?

TRUE
FALSE

6. Functional dependencies can be found out algorithmically (automatically) by analysis of the relation. No semantic analysis is required. TRUE/FALSE?

TRUE
FALSE

7. In practical terms, we want non-key attributes to be functionally dependent on the primary key in any relation. TRUE/FALSE?

TRUE
FALSE

8. Transitivity of functional dependencies means that if a →b and a→c then c→b. TRUE/FALSE?

TRUE
FALSE

9. Decomposition of functional dependencies would mean that if a→bc then a→b and a→c. TRUE/FALSE?

TRUE
FALSE

10. Functional dependencies are reflexive, i.e., if a →b then b →a. TRUE/FALSE?

TRUE
FALSE

Score =

Correct answers:

How does 2PC protocol handles failures in distributed database?

How does 2PC protocol handles failures in distributed database? / Handling participating site failure / Handling coordinator site failure / Handling network partition failure / How does Two Phase Commit protocol act to handle various failures in a distributed database?

Following are the failures that are possible in a distributed database environment. Clicking on the links that are given below will take you to the posts.

• Failure of a participating site

• Failure of a coordinator

• Network partition