Computer & IT

note!Answer: A) Database management approach
A database management approach integrates related data records and files for storage and processing.

note!Answer: D) Key field
A key field uniquely identifies each record in a file or table.

note!Answer: C) Relational database
A relational database links multiple tables through common fields (keys).

note!Answer: D) DBMS
DBMS stands for Database Management System, software used to create, retrieve and maintain database records.

note!Answer: D) Sub-schema
A sub-schema is the user's or application's view of the part of the database it needs.

note!Answer: A) Validation
Validation checks are rules that detect unsuitable or invalid data at input.

note!Answer: C) Relational
The relational model is the most widely used database model today.

note!Answer: D) All of the above
SQL statements are used to retrieve, manipulate and control data.

note!Answer: A) Number of tuples.
Cardinality of a relation is the number of tuples (rows). Degree is the number of attributes.

note!Answer: B) Non- Procedural language.
Relational calculus is a non-procedural language: it states what to retrieve, not how.

note!Answer: A) Conceptual view.
The conceptual view describes the entire database content at the logical level.

note!Answer: B) a Binary operator.
The Cartesian product combines tuples from two relations, so it is a binary operator.

note!Answer: C) Manipulation & processing of database.
DML (Data Manipulation Language) is used to retrieve, insert, update and delete data.

note!Answer: B) Rename operation.
In SQL, the AS clause gives an alias (rename) to a column or table.

note!Answer: D) Open Database Connectivity.
ODBC is Open Database Connectivity, a standard API for accessing databases.

note!Answer: C) three levels.
The ANSI-SPARC architecture has three levels: external, conceptual and internal.

note!Answer: C) Tables.
In a relational model, a relation is represented as a table.

note!Answer: C) DDL
The database schema is defined using DDL (Data Definition Language).

note!Answer: D) view level.
The external level is also called the view level; it describes user views of the data.

note!Answer: B) weak entity set.
A weak entity set lacks sufficient attributes to form a primary key and depends on a strong entity set.