varray_01.sql

SET SERVEROUTPUT ON;

DECLARE
/*
+ Array in other languages - VARRAY in PL/SQL: Collection of items of same datatype & has a maximum size. 
+ When defining a VARRAY type, you must specify its maximum size. So fixed upper bound. Subscript is integer (i.e. index) starts from 1
+ VARRAY is always dense (consecutive subscript). You cannot delete an item in middle, but we can trim elements from end. 
+ VARRAY is preferred when no. of elements known & accessed using sequence i.e. index.
*/

    TYPE va_char_type IS
        VARRAY(4) OF VARCHAR(15);
    v1  va_char_type := va_char_type('East', 'West', 'North', 'South');  -- initialize varray in declaration using constructor
    v2  va_char_type; -- Not initialized, hence this null
    v3  va_char_type := va_char_type(); -- initialize empty varray 
BEGIN

       v2 := va_char_type('North-East', 'South-East'); -- initialize varray here using constructor
    
        dbms_output.put_line('Iterating varray v1');
    FOR i IN 1..v1.count LOOP
        dbms_output.put_line('Index : '
                             || i
                             || ' and Value : '
                             || v1(i));
    END LOOP;

    dbms_output.put_line('Iterating varray v2');
    FOR i IN 1..v2.count LOOP
        dbms_output.put_line('Index : '
                             || i
                             || ' and Value : '
                             || v2(i));
    END LOOP;
    
    -- in case of v3, first lets extend (Assigning Null Values to Varray)
    v3.extend(1);
    v3(1) := 'Hello';
    v3.extend(1);
    v3(2) := 'Hello Again!';
    
        dbms_output.put_line('Iterating varray v3');
    FOR i IN 1..v3.count LOOP
        dbms_output.put_line('Index : '
                             || i
                             || ' and Value : '
                             || v3(i));
    END LOOP;

END;
/