Exchange/Move partitions between tables - oracle

Question

I have this table as my main table (100M rows):
create table prova_log(
id_dispositive number,
type number,
date_verification date,
status number
)
partition by range (date_verification) interval (NUMTODSINTERVAL(3,'DAY'))
subpartition by list (type)
subpartition TEMPLATE (
SUBPARTITION type1 VALUES (1),
SUBPARTITION type2 VALUES (2),
SUBPARTITION type3 VALUES (3),
SUBPARTITION type4 VALUES (4)
)
(
partition p0816 values less than (to_date('01/09/2016','dd/mm/yyyy'))
);
And I want to make some sort of backup with older values, so I created this (0 rows):
create table prova_log_old (
id_dispositive number,
type number,
date_verification date,
status number
)
partition by range (date_verification) interval (NUMTODSINTERVAL(3,'DAY'))
subpartition by list (type)
subpartition TEMPLATE (
SUBPARTITION type1 VALUES (1),
SUBPARTITION type2 VALUES (2),
SUBPARTITION type3 VALUES (3),
SUBPARTITION type4 VALUES (4)
)
(
partition p_old values less than (to_date('01/09/2016','dd/mm/yyyy'))
);
So I want to move/copy/exchange (whatever term) old partitions (15 days+) to prova_log_old.
To do so I've created this job:
PROCEDURE move_data_from_huge_table
IS
-- This will move all data after 'vcountdaystokeepdata' days
vcountdaystokeepdata NUMBER := 15;
vcountdatainsidepartition NUMBER := 0;
BEGIN
FOR item IN
(SELECT *
FROM (SELECT partition_name,
TO_DATE
(TRIM
('''' FROM REGEXP_SUBSTR
(EXTRACTVALUE
(DBMS_XMLGEN.getxmltype
( 'select high_value from all_tab_partitions where table_name='''
|| table_name
|| ''' and table_owner = '''
|| table_owner
|| ''' and partition_name = '''
|| partition_name
|| ''''
),
'//text()'
),
'''.*?'''
)
),
'syyyy-mm-dd hh24:mi:ss'
) high_value
FROM all_tab_partitions
WHERE table_name = 'PROVA_LOG')
WHERE high_value < SYSDATE - vcountdaystokeepdata)
LOOP
EXECUTE IMMEDIATE 'alter table PROVA_LOG EXCHANGE PARTITION '
|| item.partition_name
|| ' with table PROVA_LOG_OLD';
EXECUTE IMMEDIATE 'select count(*) from PROVA_LOG partition ('
|| item.partition_name
|| ')'
INTO vcountdatainsidepartition;
IF vcountdatainsidepartition = 0
THEN
EXECUTE IMMEDIATE 'ALTER TABLE PROVA_LOG DROP PARTITION '
|| item.partition_name
|| '';
END IF;
END LOOP;
END;
But when I run the procedure I got
ORA-14292 partitioning type of table must match subpartitioning type of composite partition
I assume that I must have a partition in my backup table with the same name as my main partitioned table right?
How can I make this work?
I tried to add a partition to my backup table but without success..It's important to mention that all partition's name are random (oracle generates it).

Answer 1

I still don't understand why you want to move the partitions, anyway I have a solution.
First of all, you can address a partition either like
SELECT COUNT(*) FROM PROVA_LOG PARTITION (SYS_P7138);
or you can do it as
SELECT COUNT(*) FROM PROVA_LOG PARTITION FOR (TO_DATE('2016-10-01', 'YYYY-MM-DD'));
or if you prefer DATE literals
SELECT COUNT(*) FROM PROVA_LOG PARTITION FOR (DATE '2016-10-01');
An automatic solution for you problem could be this one:
DECLARE
CURSOR TabPartitions IS
SELECT TABLE_NAME, PARTITION_NAME, HIGH_VALUE
FROM USER_TAB_PARTITIONS
WHERE TABLE_NAME = 'PROVA_LOG'
ORDER BY 1,2;
ts DATE;
BEGIN
FOR aPart IN TabPartitions LOOP
EXECUTE IMMEDIATE 'BEGIN :ret := '||aPart.HIGH_VALUE||'; END;' USING OUT ts;
IF ts <> DATE '2016-09-10' AND ts < SYSDATE - 15 THEN
--EXECUTE IMMEDIATE 'INSERT INTO PROVA_LOG_OLD SELECT * FROM PROVA_LOG PARTITION FOR (DATE '''||TO_CHAR(ts, 'yyyy-mm-dd')||''')';
--EXECUTE IMMEDIATE 'ALTER TABLE PROVA_LOG DROP PARTITION FOR (DATE '''||TO_CHAR(ts, 'yyyy-mm-dd')||''') UPDATE GLOBAL INDEXES';
EXECUTE IMMEDIATE 'ALTER TABLE PROVA_LOG EXCHANGE PARTITION FOR (DATE '''||TO_CHAR(ts, 'yyyy-mm-dd')||''') WITH TABLE PROVA_LOG_OLD INCLUDING INDEXES';
END IF;
END LOOP;
END;
Your backup table must be like this:
CREATE TABLE prova_log_old (
id_dispositive NUMBER,
TYPE NUMBER,
date_verification DATE,
status NUMBER
)
PARTITION BY LIST (TYPE)
(
PARTITION type1 VALUES (1),
PARTITION type2 VALUES (2),
PARTITION type3 VALUES (3),
PARTITION type4 VALUES (4)
);
or no partitioning at all
CREATE TABLE prova_log_old (
id_dispositive NUMBER,
TYPE NUMBER,
date_verification DATE,
status NUMBER
);

Answer 2

You are doing it wrong. You exchange partition with all partitioned table not with it partition, just look one more at your code
EXECUTE IMMEDIATE 'alter table PROVA_LOG EXCHANGE PARTITION '
|| item.partition_name
|| ' with table PROVA_LOG_OLD';
In case of exchange partition you should do as follows
Create empty table without partition with same structure like PROVA_LOG but not partitioned.
Exchange partition in production table with new_table
Exchange partition in hist table with new_table