Database Management System MCQs

The information about data in a database is called _______

A data dictionary is a special file that contains?

The DBMS acts as an interface between what two components of an enterprise-class database system?

A relational database system needs to maintain data about the relations, such as the schema of the relations. This is called

Relational schemas and other metadata about relations are stored in a structure called the ____________

___________ is the collection of memory structures and Oracle background processes that operates against an Oracle database.

A ________ is a logical grouping of database objects, usually to facilitate security, performance, or the availability of database objects such as tables and indexes.

A tablespace is further broken down into ________

__________ is a contiguous group of blocks allocated for use as part of a table, index, and so forth.

An Oracle __________ is a set of tables and views that are used as a read-only reference about the database.

A data dictionary is created when a __________ created.

An Oracle object type has two parts the _________ and__________

The _______ is that part of main memory available for storage of copies of disk blocks.

A major goal of the database system is to minimize the number of block transfers between the disk and memory. This is achieved by

The subsystem responsible for the allocation of buffer space is called the ___________

In the buffer where there is no space for another block, the block can be inserted using

A block that is not allowed to be written back to disk is said to be ______________

There are situations in which it is necessary to write back the block to disk, even though the buffer space that it occupies is not needed. This write is called the

In case the buffer manager do not write the blocks properly then the buffer manager uses

The technique where the blocks which have been used are replaced is called

___________________ frees the space occupied by a block as soon as the final tuple of that block has been processed.

In ordered indices the file containing the records is sequentially ordered, a ___________ is an index whose search key also defines the sequential order of the file.

Indices whose search key specifies an order different from the sequential order of the file are called ___________ indices.

An ____________ consists of a search-key value and pointers to one or more records with that value as their search-key value.

In a _______ clustering index, the index record contains the search-key value and a pointer to the first data record with that search-key value and the rest of the records will be in the sequential pointers.

In a __________ index, an index entry appears for only some of the search-key values.

Incase the indices values are larger, index is created for these values of the index. This is called

In B+ tree the node which points to another node is called

Insertion of a large number of entries at a time into an index is referred to as __________ of the index.

While inserting the record into the index, if the search-key value does not appear in the index.

If h is any hashing function and is used to hash n keys in to a table of size m, where n<=m, the expected number of collisions involving a particular key x is :

A technique for direct search is

The searching technique that takes O (1) time to find a data is

The goal of hashing is to produce a search that takes

Consider a hash table of size seven, with starting index zero, and a hash function (3x + 4)mod7. Assuming the hash table is initially empty, which of the following is the contents of the table when the sequence 1, 3, 8, 10 is inserted into the table using closed hashing? Note that ‘_’ denotes an empty location in the table.

A hash table can store a maximum of 10 records, currently there are records in location 1, 3,4,7,8,9,10. The probability of a new record going into location 2, with hash functions resolving collisions by linear probing is

What is the best definition of a collision in a hash table?

Which of the following scenarios leads to linear running time for a random search hit in a linear-probing hash table?

Breadth First Search is used in

A(n) _________ can be used to preserve the integrity of a document or a message.

A hash function must meet ________ criteria.

What is the main limitation of Hierarchical Databases?

The property (or set of properties) that uniquely defines each row in a table is called the:

The separation of the data definition from the program is known as:

In the client / server model, the database:

The database design that consists of multiple tables that are linked together through matching data stored in each table is called

The association role defines:

The purpose of an N-Ary association is:

Bitmap indices are a specialized type of index designed for easy querying on ___________

A _______ on the attribute A of relation r consists of one bitmap for each value that A can take.