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

Forward declarations - subprograms, Forward Declarations The PL/SQL ne...

Forward Declarations The PL/SQL needs that you declare an identifier before using it. And hence, you should declare a subprogram before calling it. For illustration, the decla

Parameter and keyword description - sql cursor, Parameter and Keyword Descr...

Parameter and Keyword Description: SQL: This SQL is the name of the implicit SQL cursor. %FOUND: This attribute results TRUE if an INSERT, DELETE, or UPDATE state

First step at defining type sid in sql, First Step at defining type SID in ...

First Step at defining type SID in SQL CREATE TYPE SID AS ( C VARCHAR(5) ) ; Explanation: TYPE SID announces that a type named SID is being defined to the syst

Dynamic sql - pl sql, Dynamic SQL: The Most PL/SQL programs do a predi...

Dynamic SQL: The Most PL/SQL programs do a predictable, specific job. For illustration, a stored procedure may accept an employee number and salary increase, and then update t

Projection in sql - correct version, Projection in SQL - correct version ...

Projection in SQL - correct version Student StudentId is enrolled on some course. SELECT DISTINCT StudentId FROM IS_ENROLLED_ON In more complicated examples it is someti

Keyword and parameter description in pl sql, Keyword and Parameter Descript...

Keyword and Parameter Description: label_name: This is an undeclared identifier which optionally labels the PL/SQL block. When used, label_name should be enclosed by the do

Union and or - sql, UNION and OR - SQL SQL supports UNION explicitly b...

UNION and OR - SQL SQL supports UNION explicitly but differently from the way it supports JOIN explicitly. As we have seen, JOIN is used exclusively within the FROM clause, su

Logical connectives - sql, Logical Connectives - SQL SQL's extended t...

Logical Connectives - SQL SQL's extended truth tables in which the symbol, for unknown, appears along with the usual T and F. Negation (NOT, ¬) Conjunction (

Expression in assignment statement - pl sql, Expression: This is a ran...

Expression: This is a randomly complex combination of constants, variables, literals, operators, & function calls. The simplest expression consists of a single variable. If th

Primary key, PRIMARY KEY: PRIMARY KEY  indicates that the table is sub...

PRIMARY KEY: PRIMARY KEY  indicates that the table is subject to a key constraint, in this case declaring that no two rows in the table assigned to ENROLMENT can ever have the

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