automatic partition naming for range partitioning - oracle

Question

I have a table like this
CREATE TABLE data_audit(
id_col NUMBER(*,0) NOT NULL ENABLE,
col_2 VARCHAR2(10) NOT NULL ENABLE,
col_3 NUMBER(*,0) NOT NULL ENABLE,
col_4 VARCHAR2(10) NOT NULL ENABLE,
col_5 VARCHAR2(10) NOT NULL ENABLE,
created_at TIMESTAMP (3) DEFAULT current_timestamp,
CONSTRAINT DATA_AUDIT_PK PRIMARY KEY (col_2,col_3,col_4)
USING INDEX ENABLE
)
PARTITION BY RANGE(created_at)
(
PARTITION p2022_jan
VALUES LESS THAN (TO_DATE('01-jan-2022')),
PARTITION p2022_feb
VALUES LESS THAN (TO_DATE('01-feb-2022')),
PARTITION p2022_mar
VALUES LESS THAN (TO_DATE('01-mar-2022'))
)
Here - in above example - i need to explicitly mention the name in DDL
I want to create new partition automatically for every month data
How can i achieve it naming it automatically - i am ok with any random name of partition
I am using oracle - Oracle Database 19c Enterprise Edition Release 19.0.0.0

Answer 1

Instead of a RANGE partition I would suggest an INTERVAL partition:
CREATE TABLE DATA_AUDIT (
id_col NUMBER(*,0) NOT NULL ENABLE,
col_2 VARCHAR2(10) NOT NULL ENABLE,
col_3 NUMBER(*,0) NOT NULL ENABLE,
col_4 VARCHAR2(10) NOT NULL ENABLE,
col_5 VARCHAR2(10) NOT NULL ENABLE,
CREATED_AT TIMESTAMP (3) default current_timestamp ,
CONSTRAINT DATA_AUDIT_PK PRIMARY KEY (col_2,col_3,col_4) USING INDEX ENABLE
)
partition by range (CREATED_AT) INTERVAL (INTERVAL '1' MONTH)
(PARTITION p2021_dec VALUES LESS THAN (TIMESTAMP '2022-01-01 00:00:00'));
Then Oracle will create new partition automatically every months.
For renaming you can runs this procedure by daily scheduler job as proposed by Barbaros Özhan.
PROCEDURE RenamePartitions IS
ts TIMESTAMP;
newName VARCHAR2(30);
CURSOR TabPartitions IS
SELECT TABLE_NAME, PARTITION_NAME, HIGH_VALUE
FROM USER_TAB_PARTITIONS
WHERE TABLE_NAME = 'DATA_AUDIT'
ORDER BY 1,2;
BEGIN
EXECUTE IMMEDIATE 'ALTER SESSION SET DDL_LOCK_TIMEOUT = 180';
FOR aPart IN TabPartitions LOOP
EXECUTE IMMEDIATE 'BEGIN :ret := '||aPart.HIGH_VALUE||'; END;' USING OUT ts;
ts := ADD_MONTHS(ts, -1);
newName := 'p'||TO_CHAR(ts,'yyyy_mon', 'NLS_DATE_LANGUAGE = american');
IF aPart.PARTITION_NAME <> newName THEN
EXECUTE IMMEDIATE 'ALTER TABLE '||aPart.TABLE_NAME||' RENAME PARTITION '||aPart.PARTITION_NAME||' TO '||newName;
END IF;
END LOOP;
END RenamePartitions;
Or see a more generic one: Partition table rename automatically in ORACLE

Answer 2

Assume that the table only has the first partition(p2022_jan) and you'll add new partitions to the table every month, then firstly create a stored procedure such as
CREATE OR REPLACE PROCEDURE Pr_Add_Part_to_Data_Audit is
v_ddl VARCHAR2(32767);
v_date DATE := TO_DATE(TO_CHAR(sysdate,'yyyy-mm-')||'01','yyyy-mm-dd');
BEGIN
v_ddl :='ALTER TABLE data_audit ADD PARTITION p'||TO_CHAR(v_date,'yyyy')||'_'||TO_CHAR(v_date,'mon')||' VALUES LESS THAN ('''||v_date||''')';
EXECUTE IMMEDIATE v_ddl;
END;
/
then, call that from a scheduler at the beginning of the upcoming months such as
DECLARE
v_job_name VARCHAR2(32) := 'jb_add_part_data';
BEGIN
DBMS_SCHEDULER.CREATE_JOB(job_name => v_job_name,
job_type => 'STORED_PROCEDURE',
job_action => 'Pr_Add_Part_to_Data_Audit',
start_date => TO_DATE('01-02-2021 01:00:10',
'DD-MM-YYYY HH24:MI:SS'),
repeat_interval => 'FREQ=MONTHLY; BYHOUR=1;',
auto_drop => false,
comments => 'Adds a new partition every month');
DBMS_SCHEDULER.ENABLE(v_job_name);
END;
/

Answer 3

Here the answergiven by Wernfried Domscheit - is correct
thank you for your Answer - it showed the way of controlling partition name - in my case i didn't need to care about partition name - i just needed to make sure - new partition is created with new name - so i used first half of your comment -
to verify it - i used it with DAY - partitioning
CREATE TABLE DATA_AUDIT (
id_col NUMBER(*,0) NOT NULL ENABLE,
col_2 VARCHAR2(10) NOT NULL ENABLE,
col_3 NUMBER(*,0) NOT NULL ENABLE,
col_4 VARCHAR2(10) NOT NULL ENABLE,
col_5 VARCHAR2(10) NOT NULL ENABLE,
CREATED_AT TIMESTAMP (3) default current_timestamp ,
CONSTRAINT DATA_AUDIT_PK PRIMARY KEY (col_2,col_3,col_4) USING INDEX ENABLE
)
partition by range (CREATED_AT) INTERVAL (INTERVAL '1' DAY)
(PARTITION p2021_dec VALUES LESS THAN (TIMESTAMP '2022-01-01 00:00:00'));
and then it created partitions like
partition name - table name
P2021_DEC - DATA_PURGE_AUDIT
SYS_P8592 - DATA_PURGE_AUDIT