(A) New records are added to an overflow file
(B) Multiple indexes for the same key field cannot be setup
(C) The overflow is merged with the main file during a batch update
(D) Record in main file that precedes it is updated to contain a pointer to the new record
Tag: DBMS Mcqs
Which of the following is not true with respect to denormalization?
(A) A denormalized data model is not the same as a data model that has not been normalized
(B) It is an attempt to optimize the performance of database
(C) Denormalization takes place before the normalization process
(D) None of the above
Identify the correct statement with respect to normalization.
(A) Normalization is a formal technique that can be used only at the starting phase of the database design.
(B) Normalization can be used as a top-down standalone database design technique.
(C) The process of normalization through decomposition must achieve the dependency reservation property at any cost whereas the lossless join property is sometimes sacrificed.
(D) All of the above
Suppose there are 4 fields in a table named CUST (customer_id, first_name, last_name, phone). Which of the following gives all the information of the customers in the table whose last name is ALI?
(A) SELECT * FROM CUST WHERE last_name=’ALI’;
(B) SELECT * FROM CUST WHERE last_name=ALI;
(C) SELECT * FROM CUSTOMER WHERE name=ALI;
(D) SELECT * FROM CUSTOMER WHERE last_name=ALI;
Which of the following gives all the fields from employee table named as EMP?
(A) select * from EMP;
(B) select emp* from EMP’
(C) select emp_id where EMP;
(D) select * where EMP;
Which of the following is not a feature of TRANSACTION?
(A) Users should be able to regard the execution of each transaction as atomic
(B) Each transaction, run by itself
(C) Must preserve the consistency of the database
(D) Dependant on other concurrent transactions
Which of the following is not true about De-normalization?
(A) It is the process of attempting to optimize the performance of a database
(B) De-normalization is a technique to move from lower to higher normal forms of database modeling
(C) In de-normalization it is required to add redundant data.
(D) It enhances the performance of DB
Which of the following will be deleted relating to a table if you use TRUNCATE command?
(A) Indexes
(B) All rows in a table
(C) Constraints
(D) Table structure and its columns