Help automate an UPDATE Statement with PL/SQL

Question

Hello, I am on 10g R2, I am slowly learning PL/SQL, got a few books, watching videos on youtube and other things about like Best Practices and etc. I wanted to automate this SQL:
Basically each month I have to update a whole bunch of older Tables against the current months Table.
Older Table = ta
Newer Table = tt
I was thinking maybe I can like put into a list (like an array), and list all the older tables in there for ta, I have 26 so far and each month I add +1.
The tt table is just one, that's why I was thinking I could automate that inside a loop ?
UPDATE OLDER_TABLE_DATE ta
SET (ta.GTP, ta.UPDATE_DT) =
     (SELECT tt.GTP, SYSDATE
      FROM NEWEST_TABLE_UPDATED tt
      WHERE ta.customer_id = tt.customer_id
      AND ta.STAMP_DATE = tt.STAMP_DATE)
WHERE EXISTS (SELECT 1
        FROM NEWEST_TABLE_UPDATED tt
        WHERE ta.customer_id = tt.customer_id
        AND ta.STAMP_DATE = tt.STAMP_DATE
        AND (NVL(ta.GTP, 'X') != NVL(tt.GTP, 'X')));
COMMIT;What do you guys think ? example or help would be appreciated. I can run this as an anonymous block for now, that's fine, thank you!

Answer 1

Assumptions:-
-Your all old/new tables are in same schema.
- Their names have word "OLDER".
- You will run the procedure from the same schema where all old and new tables exits.
NOTE: - Please handle exceptions in the given code accordingly, for example, when update fails then handle the exceptions.
-As mention earlier, this approach does not sound very good. A good solution will be change in design such a way that one table(partition on months) stores all the monthly data.
CREATE OR REPLACE PROCEDURE UPDATE_TABLES_PROC
AS
cursor c1 is
select table_name from user_tables
where table_name like '%OLDER%';
type t_current_table is table of c1%rowtype;
v_current_table t_current_table;
SQL_STMT VARCHAR2(3000):=0;
BEGIN
OPEN C1;
LOOP
    FETCH C1 BULK COLLECT INTO  v_current_table  LIMIT 10;
    IF v_current_table.count>0 then
    FOR i in v_current_table .first..v_current_table .last
    LOOP
    SQL_STMT:='UPDATE ' ||v_current_table(i).table_name|| ' ta
                     SET (ta.GTP, ta.UPDATE_DT) =
                                   (SELECT tt.GTP, SYSDATE
                                    FROM NEWEST_TABLE_UPDATED tt
                                    WHERE ta.customer_id = tt.customer_id
                                   AND ta.STAMP_DATE = tt.STAMP_DATE)
                      WHERE EXISTS (SELECT 1
                                   FROM NEWEST_TABLE_UPDATED tt
                                   WHERE ta.customer_id = tt.customer_id
                                   AND ta.STAMP_DATE = tt.STAMP_DATE
                                   AND (NVL(ta.GTP, ''X'') != NVL(tt.GTP, ''X'')))';
    EXECUTE IMMEDIATE SQL_STMT;
    EXIT WHEN c1%NOTFOUND;
    END LOOP;
    END IF;
COMMIT;
EXIT WHEN c1%NOTFOUND;
END LOOP;
CLOSE C1;
END UPDATE_TABLES_PROC;