Using operator value in pl sql, PL-SQL Programming

Assignment Help:

Using Operator VALUE:

As you may expect, the operator VALUE returns the value of an object. The VALUE takes its argument a correlation variable.  For illustration, to return a result set of the Person objects, you can use the VALUE as shown below:

BEGIN

INSERT INTO employees

SELECT VALUE(p) FROM persons p

WHERE p.last_name LIKE '%Smith';

In the next example, you use VALUE to return a specific Person object:

DECLARE

p1 Person;

p2 Person;

...

BEGIN

SELECT VALUE(p) INTO p1 FROM persons p

WHERE p.last_name = 'Kroll';

p2 := p1;

...

END;

At this position, p1 holds a local Person object, that is a copy of the stored object whose last name is 'Kroll', and p2 holds the other local Person object, that is a copy of p1. As the illustration below shows, you can use these variables to access and update the objects they have:

BEGIN

p1.last_name := p1.last_name || 'Jr';

Currently, the local Person object held by p1 has the last name 'Kroll Jr'.


Related Discussions:- Using operator value in pl sql

Query optimization, 1.( /5 marks) Suppose that a B+-tree index with the sea...

1.( /5 marks) Suppose that a B+-tree index with the search key (dept_name, building) is available on relation department. What would be the best way to handle the following selecti

Parameter and keyword description - object types, Parameter and Keyword Des...

Parameter and Keyword Description: type_name: This identifies a user-defined type specifier that is used in the subsequent declarations of the objects. AUTHID Clause:

What is a collection, What Is a Collection The collection is an ordered...

What Is a Collection The collection is an ordered group of elements, all of similar type (for e.g. the grades for a class of students). Each element has a unique subscript whic

Example of alternative formulation as a table constraint, Example of Altern...

Example of Alternative formulation as a table constraint Example: Alternative formulation as a table constraint ALTER TABLE EXAM_MARK ADD CONSTRAINT Must_be_enrolled_to_

Exit-when - iterative control, EXIT-WHEN The EXIT-WHEN statement permits...

EXIT-WHEN The EXIT-WHEN statement permits a loop to complete conditionally. Whenever the EXIT statement is encountered, the condition in the WHEN clause is computed. When the co

Pits, PITS Depressions in secondary cell wall is called pit. A pi...

PITS Depressions in secondary cell wall is called pit. A pit present on the free cell wall surface without its partner is called Blind pit. It consists of 2 parts -

Assignment statement in pl sql, Assignment Statement: The assignment s...

Assignment Statement: The assignment statement sets the present value of the variable, parameter, field, or element. The statement consists of an assignment target followed by

3cx pbx sync windows service, 3CX PBX sync Windows Service Project Descr...

3CX PBX sync Windows Service Project Description: !! You require access to a commercial version of the 3CX PBX system in order to be able to program the API !! !! You requ

Example of check constraints - sql, Example of Check Constraints Examp...

Example of Check Constraints Example: Workaround for when subqueries not permitted in CHECK constraints CREATE FUNCTION NO_MORE_THAN_20000_ENROLMENTS ( ) RETURNS BOOLEAN

Effects of null for table expression, Effects of NULL for Table Expression ...

Effects of NULL for Table Expression Here's an important distinction between expressions denoting tables and expressions denoting multisets of rows: a table expression cannot

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd