Yearly Partitioning a Integer column which stores Date as ID - oracle

Question

I have a table which has a DATE_ID column (Integer data type). This column basically stores dates in ID format. Input data:
DATE_ID
19961210
19991001
20051212
20090108
I need to partition this table (YEARly) based on date_id column. Please note that this is an existing process and we are migrating our tables from database to another. These column datatypes cannot be changed as they will be referred by downstream process in that fashion only.
I tried below interval partitioning but somehow didn't work. Can someone pls help?
CREATE TABLE test (date_id INT NOT NULL, text VARCHAR2(500))
PARTITION BY RANGE (DATE_ID) INTERVAL (365)
(
PARTITION P0 VALUES LESS THAN (19961231),
PARTITION P1 VALUES LESS THAN (19991231),
PARTITION P2 VALUES LESS THAN (20091231)
);

Answer 1

I got the solution:
CREATE TABLE test (
DATE_ID INTEGER
)
partition BY RANGE (DATE_ID )
interval(10000)
(partition p0 values less than(19961231),
partition p1 values less than(19991231),
partition p1 values less than(20091231)
);

Answer 2

You can add a virtual column in order to add an interval partition along with a decent date type column, and able to cross-check the eligibility of the existing integer values as been considered as date values such as
CREATE TABLE test(
date_id INT NOT NULL,
text VARCHAR2(500)
);
ALTER TABLE test ADD (dt AS ( TO_DATE(date_id,'yyyymmdd') ));
ALTER TABLE test MODIFY
PARTITION BY RANGE(dt) INTERVAL (INTERVAL '1' YEAR)
(
PARTITION P1996 VALUES LESS THAN (date'1997-01-01'),
PARTITION P1999 VALUES LESS THAN (date'2000-01-01'),
PARTITION P2009 VALUES LESS THAN (date'2010-01-01')
);
if your aim is to add yearly partition as the title implies for the year range from 1996 to 2006, then rather you can prefer using a dynamic method in order to generate the desired code block such as
DECLARE
v_ddl CLOB;
BEGIN
FOR year in 1996..2006
LOOP
v_ddl := v_ddl||' PARTITION p'||year||' VALUES LESS THAN (date'''||TO_CHAR(year+1)||'-01-01''),'||CHR(13);
END LOOP;
v_ddl := 'ALTER TABLE test MODIFY PARTITION BY RANGE(dt) INTERVAL (INTERVAL ''1'' YEAR)'||CHR(13)||'('||CHR(13)||RTRIM(v_ddl,','||CHR(13));
v_ddl := v_ddl||CHR(13)||')';
DBMS_OUTPUT.PUT_LINE(v_ddl);
EXECUTE IMMEDIATE v_ddl;
END;
/