Welcome to DataBase Quiz, Entry Level !!

Question 1. With SQL, how can you return the number of records in the "Persons" table?

SELECT COLUMNS() FROM Persons

SELECT COUNT() FROM Persons

SELECT COLUMNS(*) FROM Persons

SELECT COUNT(*) FROM Persons

Question 2. You are managing the in-house database systems. You are creating a series of secondary indexes in your relational database. By doing so, which of the following issues must be carefully considered .

confusion in selection of optimal query execution method

disk space consumption

performance overhead

All of the above

Question 3. Which SQL statement is used to delete data from a database?

TRUNCATE

DELETE

DROP

REMOVE

Question 4. Which of the following correctly describe the locking mechanism in a RDBMS?

A read lock prevents other transactions from reading the locked data

A write lock prevents other transactions from reading or writing to the locked data

Multiple transactions can have read locks on the same data item.

Either B&C

Question 5. Which SQL keyword is used to sort the result-set?

SORT BY

ORDER

ORDER BY

SORT

Question 6. In the world of SQL relational database, the data type for varchar, in general, is:

Fixed length string of n characters

Variable length string up to n characters

Floating point number of p bits precision

32-bit signed integer

Question 7. A top-to-bottom relationship among the items in a database is established by a

hierarchical schema

network schema

relational schema

all of the above

Question 8. You run a SELECT statement, and multiple duplicates of values are retrieved. What keyword can you use to retrieve only the non duplicate data?

DUBPLICATE

INDIVIDUAL

INDEX

DISTINCT

Question 9. Which of the following contains a complete record of all activity that affected the contents of a database during a certain period of time?

report writer

query language

data manipulation language

transaction log

Question 10. Which of the following types of JDBC drivers allows your Java programs to communicate with the ODBC driver of your DBMS?

Pure Java

JDBC-ODBC Bridge

Native-API

JDBC-net