Oracle 18c

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CREATE TABLE RAW_SOURCE(
  Stock  VARCHAR(100),
  Close_Date VARCHAR(100),
  Open   NUMBER,
  High   NUMBER,
  Low    NUMBER,
  Close  NUMBER,
  Volume NUMBER
);
BEGIN
/* INSERT QUERY NO: 1 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '01/01/2021', 40, 40.5, 38.5, 38.8, 83057
);

/* INSERT QUERY NO: 2 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '02/01/2021', 39.2, 39.2, 37.2, 37.8, 181814
);

/* INSERT QUERY NO: 3 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '03/01/2021', 38, 38.5, 36.5, 37, 117378
);

/* INSERT QUERY NO: 4 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '04/01/2021', 36.5, 36.6, 35.6, 35.7, 93737
);

/* INSERT QUERY NO: 5 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '05/01/2021', 35.35, 36.8, 35.1, 36.7, 169106
);

/* INSERT QUERY NO: 6 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '06/01/2021', 36.5, 38.5, 36.5, 38, 123179
);

/* INSERT QUERY NO: 7 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '07/01/2021', 37.5, 39.5, 37.3, 39.4, 282986
);

/* INSERT QUERY NO: 8 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '08/01/2021', 39, 40.5, 38.5, 40, 117437
);

/* INSERT QUERY NO: 9 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '09/01/2021', 39.7, 39.8, 39.3, 39.4, 873009
);

/* INSERT QUERY NO: 10 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '10/01/2021', 39.2, 39.2, 37.2, 37.8, 62522
);

/* INSERT QUERY NO: 11 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '11/01/2021', 38, 38.5, 36.5, 37, 114826
);

/* INSERT QUERY NO: 12 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '12/01/2021', 36.5, 37.9, 36.3, 37.8, 281461
);

/* INSERT QUERY NO: 13 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '13/01/2021', 37.5, 39.5, 37.3, 39.4, 77334
);

/* INSERT QUERY NO: 14 */
INSERT INTO RAW_SOURCE(Stock, Close_Date, Open, High, Low, Close, Volume)
VALUES
(
'XYZ', '14/01/2021', 39, 40.5, 38.5, 40, 321684
);
END;
/
1 rows affected

with data as (
select src.stock,
       src.close_date,
       src.open o,
       src.close c,
       src.high h,
       src.low l,
       lag(src.open) over (partition by src.stock order by src.close_date) o1,
       lag(src.close) over (partition by src.stock order by src.close_date) c1,
       lag(src.high) over (partition by src.stock order by src.close_date) h1,
       lag(src.low) over (partition by src.stock order by src.close_date) l1
  from raw_source src
)
select d.*,
       case when o1 > c1 and c > o and c > h1 and o < l1
            then 'Bullish Engulfing'
            when (O1 < C1) and (O > C) and (O < C1) and (C > O1) and (H < H1) and (L > L1)
            then 'Bearish Harami'
            when (O < C) and (O1 > C1) and (C > (C1 + O1)/2) and (O < C1) and (C < O1)
            then 'Piercing Line'
         end pattern
  from data d
         


STOCK
CLOSE_DATE
O
C
H
L
O1
C1
H1
L1
PATTERN


XYZ
01/01/2021
40
38.8
40.5
38.5
null
null
null
null
null

XYZ
02/01/2021
39.2
37.8
39.2
37.2
40
38.8
40.5
38.5
null

XYZ
03/01/2021
38
37
38.5
36.5
39.2
37.8
39.2
37.2
null

XYZ
04/01/2021
36.5
35.7
36.6
35.6
38
37
38.5
36.5
null

XYZ
05/01/2021
35.35
36.7
36.8
35.1
36.5
35.7
36.6
35.6
Bullish Engulfing

XYZ
06/01/2021
36.5
38
38.5
36.5
35.35
36.7
36.8
35.1
null

XYZ
07/01/2021
37.5
39.4
39.5
37.3
36.5
38
38.5
36.5
null

XYZ
08/01/2021
39
40
40.5
38.5
37.5
39.4
39.5
37.3
null

XYZ
09/01/2021
39.7
39.4
39.8
39.3
39
40
40.5
38.5
Bearish Harami

XYZ
10/01/2021
39.2
37.8
39.2
37.2
39.7
39.4
39.8
39.3
null

XYZ
11/01/2021
38
37
38.5
36.5
39.2
37.8
39.2
37.2
null

XYZ
12/01/2021
36.5
37.8
37.9
36.3
38
37
38.5
36.5
Piercing Line

XYZ
13/01/2021
37.5
39.4
39.5
37.3
36.5
37.8
37.9
36.3
null

XYZ
14/01/2021
39
40
40.5
38.5
37.5
39.4
39.5
37.3
null

STOCK	CLOSE_DATE	O	C	H	L	O1	C1	H1	L1	PATTERN
XYZ	01/01/2021	40	38.8	40.5	38.5	null	null	null	null	null
XYZ	02/01/2021	39.2	37.8	39.2	37.2	40	38.8	40.5	38.5	null
XYZ	03/01/2021	38	37	38.5	36.5	39.2	37.8	39.2	37.2	null
XYZ	04/01/2021	36.5	35.7	36.6	35.6	38	37	38.5	36.5	null
XYZ	05/01/2021	35.35	36.7	36.8	35.1	36.5	35.7	36.6	35.6	Bullish Engulfing
XYZ	06/01/2021	36.5	38	38.5	36.5	35.35	36.7	36.8	35.1	null
XYZ	07/01/2021	37.5	39.4	39.5	37.3	36.5	38	38.5	36.5	null
XYZ	08/01/2021	39	40	40.5	38.5	37.5	39.4	39.5	37.3	null
XYZ	09/01/2021	39.7	39.4	39.8	39.3	39	40	40.5	38.5	Bearish Harami
XYZ	10/01/2021	39.2	37.8	39.2	37.2	39.7	39.4	39.8	39.3	null
XYZ	11/01/2021	38	37	38.5	36.5	39.2	37.8	39.2	37.2	null
XYZ	12/01/2021	36.5	37.8	37.9	36.3	38	37	38.5	36.5	Piercing Line
XYZ	13/01/2021	37.5	39.4	39.5	37.3	36.5	37.8	37.9	36.3	null
XYZ	14/01/2021	39	40	40.5	38.5	37.5	39.4	39.5	37.3	null