Using Operator REF:

You can retrieve refs by using the operator REF that, like VALUE, takes as its argument a correlation variable. In the illustration below, you retrieve one or more refs to the Person objects, then insert the refs into the table person_refs:

BEGIN

INSERT INTO person_refs

SELECT REF(p) FROM persons p

WHERE p.last_name LIKE '%Smith';

In the later illustration, you retrieve a ref and attribute at similar time:

DECLARE

p_ref REF Person;

taxpayer_id VARCHAR2(9);

BEGIN

SELECT REF(p), p.ss_number INTO p_ref, taxpayer_id

FROM persons p

WHERE p.last_name = 'Parker'; -- must return one row

...

END;

In the final illustration, you update the attributes of a Person object:

DECLARE

p_ref REF Person;

my_last_name VARCHAR2(15);

...

BEGIN

...

SELECT REF(p) INTO p_ref FROM persons p

WHERE p.last_name = my_last_name;

UPDATE persons p

SET p = Person('Jill', 'Anders', '11-NOV-67', ...)

WHERE REF(p) = p_ref;

END;

Posted Date: 10/6/2012 8:20:37 AM | Location : United States

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