DATABASE SYSTEMS - Relational Database Management Systems - page 6

2. Data administration — Using DBMS software, it is very easy to manage database. Cen-
tralizing the administration of data can improve performance of database system when sev-
eral users share the data.
3. Data integrity and security — DBMS can provide security to databases by assigning
privileges to different users. It provides authorization or access controls to different classes
of users to perform different operations on databases, such as creation, modification, dele-
tion and updation of data. DBMS can enforce integrity constraints on the data. For example
before inserting student marks into database file, the DBMS can verify that whether student
is on roll or not. In the conventional systems because the data is duplicated in multiple files
so updating or changes may sometimes lead to entry of incorrect data in some files where
it exists.
4. Flexibility — Since changes are often necessary to the contents of the data stored in any
system, these changes are made more easily in a centralized database than in a conventional
system. Because programs and data are independent, programs do not have to be modified
when types of unrelated data are added to or deleted from the database, or when physical
storage changes.
5. Fast response to information requests — Because data are integrated into a single
database, complex requests can be handled much more rapidly then if the data were located
in separate, non-integrated files. In many businesses, faster response means better custom-
er service.
6. Efficient data and multiple accesses — A DBMS uses a variety of techniques to store
and retrieve data efficiently. DBMS allows data to be accessed in a variety of ways (such as
through various key fields) and often, by using several programming languages (both 3GL
and nonprocedural 4GL programs).
7. Lower user training costs — Users often find it easier to learn such systems and train-
ing costs may be reduced. Also, the total time taken to process requests may be shorter,
which would increase user productivity.
8. Less storage — Theoretically, all occurrences of data items need be stored only once,
thereby eliminating the storage of redundant data. System developers and database design-
ers often use data normalization to minimize data redundancy.
9. Standards can be enforced — Since all access to the database must be through DBMS,
so standards are easier to enforce. Standards may relate to the naming of data, format of