Live ORACLE

CREATE TYPE dnames_tab AS TABLE OF VARCHAR2(30);
/
CREATE TABLE depts (region VARCHAR2(25), dept_names dnames_tab)
NESTED TABLE dept_names STORE AS dnames_nt;
BEGIN
INSERT INTO depts VALUES('Europe', dnames_tab('Shipping','Sales','Finance'));
INSERT INTO depts VALUES('Americas', dnames_tab('Sales','Finance','Shipping'));
INSERT INTO depts VALUES('Asia', dnames_tab('Finance','Payroll'));
COMMIT;
END;
/
DECLARE
-- Type declaration is not needed, because PL/SQL can access the SQL object type
-- TYPE dnames_tab IS TABLE OF VARCHAR2(30); not needed
-- Declare a variable that can hold a set of department names
v_dnames dnames_tab;
-- Declare a record that can hold a row from the table
-- One of the record fields is a set of department names
v_depts depts%ROWTYPE;
new_dnames dnames_tab;
BEGIN
-- Look up a region and query just the associated department names
SELECT dept_names INTO v_dnames FROM depts WHERE region = 'Europe';
FOR i IN v_dnames.FIRST .. v_dnames.LAST
LOOP
DBMS_OUTPUT.PUT_LINE('Department names: ' || v_dnames(i));
END LOOP;
-- Look up a region and query the entire row
SELECT * INTO v_depts FROM depts WHERE region = 'Asia';
-- Now dept_names is a field in a record, so we access it with dot notation
FOR i IN v_depts.dept_names.FIRST .. v_depts.dept_names.LAST LOOP
-- Because we have all the table columns in the record, we can refer to region
DBMS_OUTPUT.PUT_LINE(v_depts.region || ' dept_names = ' ||
v_depts.dept_names(i));
END LOOP;
-- We can replace a set of department names with a new collection
-- in an UPDATE statement
new_dnames := dnames_tab('Sales','Payroll','Shipping');
UPDATE depts SET dept_names = new_dnames WHERE region = 'Europe';
-- Or we can modify the original collection and use it in the UPDATE.
-- We'll add a new final element and fill in a value
v_depts.dept_names.EXTEND(1);
v_depts.dept_names(v_depts.dept_names.COUNT) := 'Finance';
UPDATE depts SET dept_names = v_depts.dept_names
WHERE region = v_depts.region;
-- We can even treat the nested table column like a real table and
-- insert, update, or delete elements. The TABLE operator makes the statement
-- apply to the nested table produced by the subquery.
INSERT INTO TABLE(SELECT dept_names FROM depts WHERE region = 'Asia')
VALUES('Sales');
DELETE FROM TABLE(SELECT dept_names FROM depts WHERE region = 'Asia')
WHERE column_value = 'Payroll';
UPDATE TABLE(SELECT dept_names FROM depts WHERE region = 'Americas')
SET column_value = 'Payroll' WHERE column_value = 'Finance';
COMMIT;
END;
/

Using INSERT, UPDATE, DELETE, and SELECT Statements With Nested Tables