Inserting objects in pl sql, PL-SQL Programming

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Inserting Objects:

You can use the INSERT statement to add objects to an object table. In the illustration below, you insert a Person object into the object table persons:

BEGIN

INSERT INTO persons

VALUES ('Jenifer', 'Lapidus', ...);

Or else, you can use the constructor for the object type Person to insert an object into the object table persons:

BEGIN

INSERT INTO persons

VALUES (Person('Albert', 'Brooker', ...));

In the later illustration, you use the RETURNING clause to store the Person refs in local variables. Note that how the clause mimics a SELECT statement. The RETURNING clause can also use in the UPDATE and DELETE statements.

DECLARE

p1_ref REF Person;

p2_ref REF Person;

...

BEGIN

INSERT INTO persons p

VALUES (Person('Paul', 'Chang', ...))

RETURNING REF(p) INTO p1_ref;

INSERT INTO persons p

VALUES (Person('Ana', 'Thorne', ...))

RETURNING REF(p) INTO p2_ref;

To insert the objects into an object table, you can use a sub query which returns objects of the similar type. The illustration is as shown below:

BEGIN

INSERT INTO persons2

SELECT VALUE(p) FROM persons p

WHERE p.last_name LIKE '%Jones';

The rows copied to another object table persons2 are given the new object identifiers. The object identifiers are not copied from the object table persons. The scripts below create a relational table named department that has a column of the type Person, and then inserts a row into the table. Note that how constructor Person () gives a value for the column manager.

CREATE TABLE department (

dept_name VARCHAR2(20),

manager Person,

location VARCHAR2(20))

/

INSERT INTO department

VALUES ('Payroll', Person('Alan', 'Tsai', ...), 'Los Angeles')

/


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