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

Procedures in pl/sql, Procedures   The procedure is a subprogram which...

Procedures   The procedure is a subprogram which performs a specific action. You write procedures using the syntax as shown below: PROCEDURE name [(parameter[, parameter, .

Operators on tables and rows, Operators on Tables and Rows Row Extrac...

Operators on Tables and Rows Row Extraction TUPLE FROM r, SQL has row subqueries. These are just like scalar subqueries except that they may specify more than one column.

Declare keyword description in pl sql, DECLARE : This keyword signals t...

DECLARE : This keyword signals the beginning of the declarative section of the PL/SQL block, that contains local declarations. The Items declared locally exist only within the

Packages, Packages The package is a schema object which groups logicall...

Packages The package is a schema object which groups logically associated to the PL/SQL items, types, and subprograms. The Packages have 2 sections: the specification & the bod

Using not null-declarations in sql, Using NOT NULL Besides assigning an ...

Using NOT NULL Besides assigning an initial value, the declarations can impose the NOT NULL constraint, as the example below shows: acct_id INTEGER(4) NOT NULL := 9999; You ca

Data types in sql - interval, Data Types in SQL - Interval, Boolean I...

Data Types in SQL - Interval, Boolean INTERVAL for values denoting, not intervals (!) but durations in time, such as 5 years, 3 days, 2 minutes, and so on. BOOLEAN, con

Parameter and keyword description - records, Parameter and Keyword Descript...

Parameter and Keyword Description: record_type_name: This identifies the user-defined type specifier that is used in the subsequent declarations of the records. NOT N

Explicit cursors, Explicit Cursors The set of rows returned by the que...

Explicit Cursors The set of rows returned by the query can include zero, one, or multiple rows, depending on how many rows meet your search criteria. Whenever a query returns

Using savepoint, Using SAVEPOINT The SAVEPOINT names and marks the pre...

Using SAVEPOINT The SAVEPOINT names and marks the present point in the processing of a transaction. Used with the ROLLBACK TO statement, the savepoints undo parts of a transac

Using operator value in pl sql, Using Operator VALUE: As you may expec...

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

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