Plsql variables

When declaring variables you must also specify the block where the variables are going to be used.

• attrId = Variable name
• ':=' = Sets the variable to a value

DECLARE 
    attrId number;
BEGIN
    attId:= seq_attr.nextval;
    dbms_output.put_line (attId);
END;

Collections

Collections are more of an array then a TABLE. In the example below MyListType is just the name of the array type and it is declared to the variable myList.

myList.FIRST = The first option in the list, example 'option1'

myList.LAST = The last option in the list, example 'option3'

x = The index in the array.

DECLARE
TYPE MyListType IS TABLE OF VARCHAR(21);

myList MyListType := MyListType('option1', 'option2', 'option3');

BEGIN

  FOR x IN myList.FIRST .. myList.LAST
  LOOP

      dbms_output.put_line('MyList:' || myList(x));
   
  END LOOP;  

END;

SELECT INTO

You can set a variable from a query by using INTO.

DECLARE

    v_count NUMBER;
    v_total NUMBER;

BEGIN

    select count(id) INTO v_count FROM user;

END;