Q & A - Computer Science

Q & A

• A lock that prevents the use of any tables in the database from one transaction while .... A lock that prevents the use of any tables in the database from one transaction while another transaction is being processed is called a (a)  database-level lock        ...
• Which property of transaction ensures that either all operations of the transaction are... Which property of transaction ensures that either all operations of the transaction are reflected properly in the database or none are? (a)  Atomicity                   ...
• The following incomplete SQL statement, once completed, is expected to be used to retrieve The following incomplete SQL statement, once completed, is expected to be used to retrieve all employees who have not worked on at least one project? SELECT EMP_ID FROM ...
• A condition that occurs when two transactions wait for each other to unlock data is known. A condition that occurs when two transactions wait for each other to unlock data is known as a(n) (a)  shared lock                                      (b)  exclusive lo...
• The file organization which allows us to read records that would satisfy..... The file organization which allows us to read records that would satisfy the join condition by using one block read is (a)  Heap file organization                       ...
• A unit of storage that can store one or more records in a hash file organization is.... A unit of storage that can store one or more records in a hash file organization is denoted as (a)  Buckets             (b)  Disk pages       (c)  Blocks              (d...
• Which level of RAID refers to disk mirroring with block striping? Which level of RAID refers to disk mirroring with block striping? (a)  RAID level 1                                     (b)  RAID level 2                             (c)...
• What is the model moved conceptual modeling into the practical design arena by establishin What is the model moved conceptual modeling into the practical design arena by establishing the basic building blocks: entities and relationships. (a)  Rein85           ...
• A logical description of some portion of database that is required by a user to perform. A logical description of some portion of database that is required by a user to perform task is called as. (a)  User View          (b)  Logical View                     ...
• Which of the following attribute is an attribute that can be further subdivided to yield . Which of the following attribute is an attribute that can be further subdivided to yield additional attributes? (a)  Composite                                       (b) ...
• Making a change to the conceptual schema of a database but not affecting the existing. Making a change to the conceptual schema of a database but not affecting the existing external schemas is an example of (a)  Physical data independence             (b)  ...
• A relation that has no partial dependencies .It is in which normal form. A relation that has no partial dependencies .It is in which normal form. (a)  First                  (b)  Second             (c)  Third                 (d)  Fourth      ...
• Which of the following constraint specifies the number of instances of entity B that may a Which of the following constraint specifies the number of instances of entity B that may associate each instance of entity? (a)  Stability             (b)  Entity       ...
• What is the hierarchical database model uses the hierarchic sequence that always starts at What is the hierarchical database model uses the hierarchic sequence that always starts at? (a)  The right side of the tree                   (b)  The left side of the t...
• Which of the following key is an attribute in relation of a database that serves as the pr Which of the following key is an attribute in relation of a database that serves as the primary key of another relation in the same database? (a)  Composite Key         ...
• DBMS allows you to extrapolate information from your data by using . DBMS allows you to extrapolate information from your data by using (a)  Query language (b)  Table generator                                (c)  Security system (d)  Acc...
• Application programs that are used to create and maintain the database and provide . Application programs that are used to create and maintain the database and provide information to the users is called as (a)  FILE                  (b)  DBMS            ...
• ___­­­­­­_____is a unit program execution that can be accessed and possibly updated variou ___­­­­­­_____is a unit program execution that can be accessed and possibly updated various data items. (a)  Transactions     (b)  File                   (c)  Database  ...
• The Subsystems responsible for the allocation of buffer space is called __________ The Subsystems responsible for the allocation of buffer space is called __________ (a)  Buffer manager                               (b)  Cache manager                 (...
• _________ is a predicate expressing a condition that always must be satisfied. _________ is a predicate expressing a condition that always must be satisfied. (a)  Assertion                                        (b)  Trigger              (c)  Proce...
• _______ constraints maintains uniqueness in a record. _______ constraints maintains uniqueness in a record. (a)  Entity integrity   (b)  Referential Integrity              (c)  Domain Integrity (d)  Check integrity  (e)  None.
• A database spread among a network of geographically separated location is. _______________ A database spread among a network of geographically separated location is. ____________________ (a)  OODBMS                                       (b)  Network DBMS      ...
• _______ is a procedural language for manipulating relations. _______ is a procedural language for manipulating relations. (a)  Relational algebra                            (b)  Rational algebra                               (c)  ...
• _______ is a set of statements that allows SQL to be used with traditional programming lan _______ is a set of statements that allows SQL to be used with traditional programming languages. (a)  Common SQL                                 (b)  Embedded SQL      ...
• Any set of attributes that uniquely identifies each tuple in a relation is termed as _____ Any set of attributes that uniquely identifies each tuple in a relation is termed as _________ (a)  Foreign key      (b)  Primary key       (c)  Super key          (d)  ...
• A row in a relation is called A row in a relation is called (a)  Record             (b)  Entity                (c)  Tuple                 (d)  Table                (e)  Data.
• The relational database model presents data in the form of __________ The relational database model presents data in the form of __________ (a)  Table                (b)  Record              (c)  Entities              (d)  Objects         ...
• The term ______is widely used to refer to older applications in an organization that are b The term ______is widely used to refer to older applications in an organization that are based on file processing. (a)  Old systems                                   (b)...
• A logical description of some portion of database that is required by a user to perform ta A logical description of some portion of database that is required by a user to perform task is _______ (a)  User View         (b)  Logical View      (c)  System        ...
• _________ Model describes entities, relationships and attributes. _________ Model describes entities, relationships and attributes. (a)  E – R Model     (b)  Functional         (c)  Relational          (d)  Network         (e)  Info logical.
• ___________ controls are incorporated in the data management system that restrict access t ___________ controls are incorporated in the data management system that restrict access to data and also restrict actions that people may take when they access data. (a...
• A relation that has no partial dependencies is in __________ normal form. A relation that has no partial dependencies is in __________ normal form. (a)  First                 (b)  Second             (c)  Third                 (d)  Fourth      ...
• A ____ constraint specifies the number of instances of entity B that may associated each i A ____ constraint specifies the number of instances of entity B that may associated each instance of entity. (a)  Stability            (b)  Entity                (c)  Or...
• The goal of ____ is the protection of data from accidental or international threats to its The goal of ____ is the protection of data from accidental or international threats to its integrity and access. (a)  Rollback           (b)  Integrity             (c)  ...
• A __________ is an attribute in relation of a database that serves as the primary key of a A __________ is an attribute in relation of a database that serves as the primary key of another relation in the same database. (a)  Composite Key                       ...
• Data that describes the properties or characteristics of other data is called ____________ Data that describes the properties or characteristics of other data is called ______________ (a)  Main data         (b)  Meta Data         (c)  Primary             (d)  ...
• Application programs that are used to create and maintain the database and provide informa Application programs that are used to create and maintain the database and provide information to users is called as ______________ (a)  FILE                 (b)  DBMS  ...
• Which of the following is not true about B+ trees?. Which of the following is not true about B trees? (a)B tree index takes the form of balanced tree (b)Performance of B tree degrades as the file grows (c)Look-up in B...
• Which of the following facility is used by DBMS that periodically suspends all processing Which of the following facility is used by DBMS that periodically suspends all processing and synchronizes its files and journals? (a)Checkpoint facility (b)Backup fa...
• What is the extent of the database resource that is included with each lock called? What is the extent of the database resource that is included with each lock called? (a)Level of impact (b)Granularity (c)Management (d)Dbms control (e)Recovery.
• The means that data used during the execution of a transaction cannot be used by a second. The means that data used during the execution of a transaction cannot be used by a second transaction until the first one is completed is called (a)Serializability (b...
• Which of the following statement(s) is/are true for two-phase locking? Which of the following statement(s) is/are true for two-phase locking? I.     Lock acquisition is the second phase II.     Locks can be acquired at any time III.    ...
• What is the result of the following query? SELECT FLOOR(3.6) FROM DUAL?. What is the result of the following query?  SELECT FLOOR(3.6) FROM DUAL? (a)3.5 (b)3.0 (c)4.0 (d)3.7 (e)3.4.
• Which of the following is not an ACID property? Which of the following is not an ACID property? (a)Atomicity (b)Concurrency (c)Isolation (d)Durability (e)Serializability.
• Which of the following lock prevents the use of any tables in the database from one transa Which of the following lock prevents the use of any tables in the database from one transaction while another transaction is being processed? (a)Database-level lock (...
• Which of the following is true with respect to the B+ tree index method? Which of the following is true with respect to the B tree index method? (a)Records are physically stored in primary key order (b)B trees use a hashing algorithm (c)T...
• The file organization which allows us to read records that would satisfy the join.  The file organization which allows us to read records that would satisfy the join condition by using one block read is (a)Heap file organization (b)Sequential file o...
• The unit of storage that can store one are more records in a hash file organization are The unit of storage that can store one are more records in a hash file organization are (a)Buckets (b)Disk pages (c)Blocks (d)Nodes (e)Baskets.
• In the ANSI/SPARC three level database model, the external view is best described by which In the ANSI/SPARC three level database model, the external view is best described by which  of the following options? (a)It is the link between users and the storage s...
• Which of the following best describes the internal level of the ANSI/SPARC three level . Which of the following best describes the internal level of the ANSI/SPARC three level architecture? (a)The internal level is concerned with the layout of records an...