CREATE TYPE EMA_ROW AS OBJECT ( T_TIME VARCHAR2(50), EMA NUMBER );

CREATE TYPE EMA_TAB IS TABLE OF EMA_ROW;

CREATE OR REPLACE FUNCTION GET_EMA_TAB () RETURN
EMA_TAB PIPELINED
IS
  AMOUNT NUMBER;
BEGIN
  SELECT COUNT(*) INTO AMOUNT FROM RTS_PRICE;
  FOR i IN 1 .. AMOUNT LOOP
    PIPE ROW(t_tf_row(i, 'Description for ' || i));
  END LOOP;
  RETURN;
END GET_EMA_TAB;


SELECT * FROM RTS_PRICE


CREATE OR REPLACE FUNCTION GET_EMA(I IN NUMBER, N IN NUMBER) RETURN NUMBER
IS
  F_PRICE NUMBER;
BEGIN
  SELECT PRICE INTO F_PRICE FROM RTS_PRICE;
  IF n < 2
    THEN RETURN F_PRICE;
    ELSE RETURN GET_EMA(I - 1, N) + (F_PRICE - GET_EMA(I - 1, N)) * 2 / N;
  END IF;
END GET_EMA;

CREATE OR REPLACE PROCEDURE FILL_EMA
IS
  PREV NUMBER;
  CURR NUMBER;
BEGIN
  select NVL(MIN(PRICE), 0) INTO PREV from (select PRICE from RTS_PRICE order by TICK_TIME) where rownum = 1;
  FOR vItems IN (
      SELECT TICK_TIME, PRICE
      FROM RTS_PRICE
      ORDER BY TICK_TIME
   )
   LOOP
       CURR := PREV + (vItems.PRICE - PREV) * 2 / 10;
       INSERT INTO EMA_T(TICK_TIME, PRICE) VALUES(vItems.TICK_TIME, CURR);
       PREV := CURR;
   END LOOP;
  RETURN;
END FILL_EMA;

begin
    FILL_EMA;
end;

SELECT * FROM RTS_PRICE

--------------------------------------------------------------------------------
CREATE TABLE EMA_T(
    TICK_TIME VARCHAR2(100),
    PRICE NUMBER
);

DROP TABLE EMA_T;
SELECT * FROM EMA_T

select * from (select * from RTS_PRICE
order by TICK_TIME)
where rownum = 1;

SELECT MIN(PRICE) FROM RTS_PRICE ORDER BY TICK_TIME
select MIN(PRICE) from (select PRICE from RTS_PRICE order by TICK_TIME) where rownum = 1;
  select NVL(MIN(PRICE), 0) from (select PRICE from RTS_PRICE order by TICK_TIME) where rownum = 1;

SELECT * FROM EMA_T;
SELECT COUNT(*) FROM RTS_PRICE


SELECT * FROM RTS_PRICE
SELECT * FROM EMA_T

CREATE VIEW RTS_EMA AS SELECT RTS_PRICE.TICK_TIME, RTS_PRICE.PRICE RTS_PRICE, EMA_T.PRICE EMA_PRICE FROM RTS_PRICE, EMA_T WHERE RTS_PRICE.TICK_TIME = EMA_T.TICK_TIME