Role of abstraction in pl/sql, PL-SQL Programming

Role of Abstraction in pl/sql:

The abstraction is a high-level description or model of a real-world entity. The Abstractions keep our daily lives convenient. They help us cause about an object, event, or relationship by suppressing the irrelevant detail. For illustration, to drive a car, you do not require to know how its engine works. The simple interface consisting of a steering wheel, gearshift, accelerator, and brake, lets you use the car efficiently. The details of what happens under the hood are not significant for day-to-day driving.

The Abstractions are central to the discipline of programming. For illustration, you use the procedural abstraction when you suppress the details of a complex algorithm by writing a procedure and passing it parameters. A single procedure call hides the particulars of your implementation. To try a special implementation, you simply replace the procedure with the other having similar name and parameters. Thanks to the abstraction, programs that call the procedure need not be customized.

You use the data abstraction when you state the datatype of the variable. The datatype stipulate a set of values and a set of operations suitable for those values. For illustration, a variable of the type POSITIVE can hold only the positive integers, and can only be added, multiplied, and subtracted, and so on. To use the variable, you do not require knowing how the PL/SQL stores integers or implements arithmetic operations; you basically accept the programming interface.

The Object types are a generalization of the built-in datatypes found in many programming languages. The PL/SQL gives a variety of the built-in scalar and composite datatypes, each of that is associated with the set of predefined operations. The scalar type (like CHAR) has no internal components. The composite type (like the RECORD) has internal components which can be manipulated separately. Similarly the RECORD type, an object type is a composite type. Though, its operations are user-defined, and not predefined.

Presently, you cannot define object types within the PL/SQL. They should be CREATED and stored in an Oracle database, where they can be shared by a lot of programs. A program which uses the object types is known as the client program. It can manipulate and declare an object without knowing how the object type presents data or implements operations. This permits you to write the program and object type individually, and to change the implementation of the object type without affecting the program. And hence, the object types support both the procedural and data abstraction.

Posted Date: 10/6/2012 7:51:15 AM | Location : United States







Related Discussions:- Role of abstraction in pl/sql, Assignment Help, Ask Question on Role of abstraction in pl/sql, Get Answer, Expert's Help, Role of abstraction in pl/sql Discussions

Write discussion on Role of abstraction in pl/sql
Your posts are moderated
Related Questions
Quantification in SQL To quantify something, as the theory book has it, is to state its quantity, to say how many of it there are. For example, in Tutorial D the expression CO

a. Create a table odetails_new. It has all the attributes of odetails and an additional column called cost, whose values are the product of the quantity and price of the part bein

Tautologies: Above given table allows us to read the truth of the connectives in the next manner. Just expect we are looking at row three. It means this says that, if there P

LEVEL You use the LEVEL with the SELECT CONNECT BY statement to categorize rows from a database table into a tree structure. The LEVEL returns the level number of a node in a

Product-specific Packages The Oracle and different Oracle tools are supplied with the product-specific packages which help you to build the PL/SQL-based applications. For illus

How Bulk Binds Improve Performance The assigning of values to the PL/SQL variables in SQL statements is known as binding. The binding of the whole collection at once is know

Oracle 11 G new features associated with this release:- Enhanced ILM  - Information Lifecycle Management (ILM) has been around for the almost 10 years, but Oracle has made

Anatomy of a Command Figure, showing a simple SQL command, is almost identical to its counterpart in the theory book. The only difference arises from the fact that SQL uses a

IF Statement The IF statement executes a series of statement conditionally. Whether the series is executed or not depends on the value of the Boolean expression. Syntax:

%ROWCOUNT The %ROWCOUNT yields the number of rows affected by the INSERT, UPDATE, or DELETE statement, or returned by a SELECT INTO statement. The %ROWCOUNT yields zero when a