Data Modeling and Database Design Chapter One
____________________ are an organized conglomeration of user-specified restrictions on the organization's activities (business processes) that must be reflected in the database and/or database applications.
Business rules
____ in file-processing systems not only creates maintenance inefficiencies, but also leads to the problem of not knowing which is the current, correct data.
Data redundancy
Data does not necessarily need to be organized in order to be accessed from a database
False
Data modeling is no longer a necessary part of the database design process due to the recent emergence of new database design technologies.
False
One objective of database systems is to establish program-data dependence.
False
The DML compiler makes use of the data dictionary to look up the required data component structures and relationships.
False
The conceptual data model describes the structure of the data to be stored in the database and specifies how and where it will be physically stored and the methods used to retrieve it.
False
The external schema is concerned with efficiency of data storage and access mechanisms in the database.
False
The second tier of the data modeling activity is called lateral design.
False
____ data independence enables a user view to be immune to changes in the other user views.
Logical
____ has been established as the language for accessing data in a database by the International Organization for Standardization (ISO) and the American National Standards Institute (ANSI).
SQL
Database systems seek to overcome the two root causes of the limitations that plague file-processing systems by creating a single integrated set of files that can be accessed by all users.
True
Despite today's sophisticated information technologies, there are still only two primary approaches for accessing data.
True
File-processing systems are dependent upon a programmer who either has to write or modify program code to meet these information requirements from isolated data.
True
In the absence of a conceptual schema, the internal schema structures are necessarily mapped directly to external views.
True
Physical design involves using the tools of a particular DBMS product to create the database and to design and develop applications that address the high-level requirements of the universe of interest.
True
The DBMS accesses the database and supplies data appropriate to the needs of individual application programs.
True
The ____ handle database access at run time by passing requests to the file manager of the operating system to retrieve data from the physical files of the database.
access routines
During the conceptual design, the focus should be on capturing the user-specified ____.
business rules
By insulating applications/programs from changes in physical storage structure and data access strategy, the ____ schema achieves program-data independence in a database environment.
conceptual
____ language is used to create the structure of database objects such as tables, views, and synonyms.
data definition
In the database design arena, a ____ is used to represent real-world phenomena.
data model
The ____________________ is a collection of metadata about data models and application program interfaces.
data repository
A file is sometimes referred to as a(n) ____________________ .
data set
In a file-processing system, data is separated and isolated, and ownership of data is compartmentalized, resulting in limited ____.
data sharing
A(n) ____________________ is a self-describing collection of interrelated data.
database system
Data management involves four actions: data creation, data retrieval, data modification or updating, and data ____.
deletion
When a single-user database runs on a personal computer, it is also called a(n) ____ database system.
desktop
A(n) ____________________ is a collection of multiple logically interrelated databases that may be geographically dispersed over a computer network.
distributed database
The ____________________ consists of a number of different user views or subschemas, each describing portions of the database of interest to a particular user or group of users.
external schema
Data ____________________ is when the conceptual schema insulates user views from changes in the physical storage structure of the data.
independence
For direct access, the records in a file can be stored serially and be organized either randomly or using an external ____.
index
____________________ is data that has been organized into a specific context such that it has value to its recipient.
information
Data ____ ensures that data is consistent, accurate, and reliable.
integrity
In a file-processing system, the programmer's view corresponds to the physical structure of the data or ____ schema.
internal
The ____ schema is technology-dependent.
internal
The ____________________ describes the physical structure of the stored data and the mechanism used to implement the access strategies.
internal schema
____________________ independence enables a user view to be immune to changes in the other user views.
logical data
The product of the logical design activity is the ____.
logical schema
____________________ contains a complete definition or description of database structure, and other constraints on the stored data.
metadata
To facilitate sequential access, all records in a file must be stored ordered ____.
on some unique identifier
Database design follows a life cycle that includes three tiers: conceptual data modeling, logical data modeling, and ____ data modeling.
physical
Once a logical schema has been developed, the process moves on to the ____ design tier.
physical
Most DBMS products include ____ language extensions to supplement the capabilities of SQL, such as Oracle PL/SQL.
procedural
A set of values for the data elements constituting a record type is called a record instance or simply a(n) ____________________.
record
A group of related data elements treated as a unit is called a(n) ____________________.
record type
A company with ten plants might have a PLANT file or a PLANT data set that contains ten ____.
records
The initial step in the design process is the ____ specification.
requirements
____________________ access is where in order to get to the nth record in a data set it is necessary to pass through the previous n-1 records in the data set.
sequential
It is imperative that a ____ step is included as the concluding activity in the conceptual modeling phase.
validation
