Database Management System (DBMS) Interfaces:
Definition and Explanation:
The user manipulates the data of database
through, user-interface. There are following data access interfaces used for
manipulating data of database.
1. Data manipulation by means of forms.
2. Application program interface.
3. Query language interface.
4. Stored procedures.
1. Data Manipulation By Means of Forms:
A Form-based interface is used to enter data into
database or to display data. Typically, the user sends request to the DBMS to
retrieve specific records or update records of database. Most DBMSs include
tools for creating Forms. You can create Form to access data of single table or
multiple tables.
2. Application Program Interface:
The application programs play very important role
in data manipulations of databases. Every application program provides a
user-interface. The end-users interact with the DBMS through the interface of
application program to perform various operations on the database. The
application programs are written in programming languages such as Visual Basic,
C++, and Java etc.
3. Query Language Interface:
Query language also provides the user-interface
to interact with the DBMS. Usually, it is a command-line interface. With this
type of interface, the user enters query command to perform a specific action on
the database (manipulate the data of database). The DBMS decodes the command and
carries out an appropriate action.
The most popular query language is SQL. The commands or statements of this language are similar to English statements.
Example:
To retrieve all those records of 'STUDENT table that have value 'L' in
the column 'City', the SQL Select statement is written as;
SELECT Roll_No, name, city FROM student .
WHERE city = 'L'
4. Stored Procedures:
Stored procedures are the collections of SQL
statements (or statements of any other database language) stored on database
server as a file and can be called for manipulating data by using a single
command. Parameters can also be passed to these procedures. A special type of
stored procedure, known as trigger, is called by the DBMS when a specified
condition occurs.
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