Explore topic-wise MCQs in Engineering.

Relationships cannot have attributes.

Business rules and policies are universal.

An enterprise key is a primary key whose value is unique for a given relation.

A composite attribute does not get mapped into a relation.

A relation is a two-dimensional table.

Weak entities do not get mapped into a relation.

Database administration refers to a function that applies to the entire organization.

The transaction log contains a copy of every database record (or page) after it has changed. These records are called before images.

A primary key may be null.

The goal of database security is to ensure that only authorized users can perform authorized activities at authorized times.

A phantom read occurs when a transaction rereads data it has previously read and finds modifications or deletions caused by a committed transaction.

A transaction is a series of actions to be taken on the database so that either all of them are performed successfully or none of them are performed at all.

Two transactions that run concurrently and generate results that are consistent with the results that would have occurred if they had run separately are referred to as serializable transactions.

A point of synchronization between the database and the transaction log is generally referred to as a stop point.

An exclusive lock locks the item from change but not from read.

When one transaction reads a changed record that has not been committed to the database a filthy read occurs.

The size of a lock is referred to as lock sizing.

Locks placed by command are implicit locks.

Locks placed by the DBMS are explicit locks.

In optimistic locking, the assumption is made that conflict will occur.

To build a data warehouse and develop business intelligence applications, it is important that an organization build and maintain a comprehensive repository.

Failure to control confidentiality may lead to loss of competitiveness.

Resource locking is a process to prevent multiple applications from obtaining copies of the same record when the record is about to be changed.

The overall responsibility of the DBA is to facilitate the development and use of the database.

The size of the lock is referred to as the lock granularity.

A durable transaction is one in which all committed changes are permanent.

An ACID transaction is one that is atomic, consistent isolated, and durable.

Both status data and event data can be stored in a database.

Static extract is used for ongoing warehouse maintenance.

A SQL view is a virtual table that is constructed from other tables or views.

There are three SQL data modification operations: insert, modify and delete.

SQL statements can be embedded in triggers, stored procedures, and program code.

Three types of triggers are: BEFORE, AFTER and EXCEPTION.

A view that contains a computed column can be easily updated.

A trigger is a stored program that is attached to a database.

When a foreign key column is created without a corresponding foreign key constraint, we have created a "casual relationship" between the two tables.

Views can be used to show the results of computed columns.

A benefit of using a stored procedure is that it can be distributed to client computers.

A stored procedure is a program that performs some common action on database data and is stored in the database.

SQL Server does not support the BEFORE trigger.

A updatable view has its own data.

The SQL DELETE statement is used to delete both the table structure and table data.

Common types of SQL CHECK constraints include range checks and limiting columns values.

If any required (NOT NULL) columns are missing from the view, the view cannot be used for inserting new data.

Generalization is the process of defining more general entity types from a set of more specialized entity types.

It is appropriate to use a supertype/subtype relationship when there are attributes that apply to some of the instances of an entity type.

Action assertions have traditionally been implemented within an application program.

An entity cluster is a set of one or more entity types and associated relationships.

Overlapping and disjoint subtypes have different approaches on how the subtype discriminator is applied.

A supertype is an entity type that shares common attributes or relationships distinct from other subgroupings.