What is the importance on insulation between programs, data and data
abstraction.  Is this more important to database administrators,
database designers or end users?

Hi 888-ga, 

I'm going to start with the second part of you question (momma always
said I did everything bass ackwards ;) because it's a bit subjective.

Is this more important to database administrators, database designers
or end users?

I think I'll let you decide that, because it is important to all of
them and I could not decide who it is MORE important to.

It is important Database Administrators because:
The structure of data files is stored in the DBMS catalog separately
from the access programs. (See paragraph 1 in the explanation below)

It is important Database designers because:
The implementation of the operation is specified separately and can be
changed without affecting the interface.
(See paragraph 2 in the explanation below)

It is important End users because:
A data model hides storage details and present the users with a
conceptual view of the database, which describes only the data of
interest to that user.
(See paragraph 3 in the explanation below)

Database systems
Basic Concepts
http://www.cs.appstate.edu/~rt/DBMS/notes/chap1.pdf

Insulation between Programs and Data, and Data Abstraction

1)  In traditional file processing, the structure of data files is
embedded in the access programs.
Thus, any change to the structure of a file may require changing all
programs that access this file.
Database management system (DBMS) access programs do not require such
changes in most cases. The structure of data files is stored in the
DBMS catalog separately from the access programs. This property is
called program-data independence.

2) There are times that a database is designed such that an operation
on the database is defined in two parts; one part is the operation
name and the other data type of the arguments (or parameters).
The implementation of the operation is specified separately and can be
changed without affecting the interface.

User application programs can operate on the data by invoking these
operations through their names and arguments, regardless, of how the
operations are implemented. This is known as program-operation
independence.

The characteristic that allows program-data independence and
program-operation independence is called Data Abstraction.

3) A DBMS provides users with a conceptual representation of data that
includes many of the details of how the data is stored or how the
operations are implemented.
A data model is a type of data abstraction that is used to provide
this conceptual representation.
A data model hides storage and implementation details that are not of
interest to most database users.

Additional resources:

Databases and Database users
http://netdb.chungbuk.ac.kr/Note/DB/4

Databases and Database Management Systems
Fundamentals of Database Systems
http://www.cc.gatech.edu/classes/AY2002/cs6400_spring/FILE1_revised_wf.pdf

Database Technology
http://www.ida.liu.se/~TDDB38/2001/ALL-DB-COURSES/CourseMaterial/Introduction_2001a.OH.pdf

DBMS Architecture and Data Independence
http://www.cs.uofs.edu/~mccloske/courses/cmps341/en_chap2_lec.html

Introductory Concepts
http://www.utdallas.edu/~lkhan/Fall2001/Class1.doc

Databases and Database Users 
http://www.valdosta.edu/~sfares/cs480/cs4xx.chapter1.fa7.html

~wlk115

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Funny to see the rating comment: "a lot of content can be found from
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