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Update multiple table column values using single query

开发者 https://www.devze.com 2022-12-28 01:41 出处:网络
How would you update data in multiple tables using a single query? MySQL Example The equivalent code in MySQL:

How would you update data in multiple tables using a single query?

MySQL Example

The equivalent code in MySQL:

UPDATE party p
LEFT JOIN party_name n ON p.party_id = n.party_id
LEFT JOIN party_details d ON p.party_id = d.party_id
开发者_如何学编程LEFT JOIN incident_participant ip ON ip.party_id = p.party_id
LEFT JOIN incident i ON ip.incident_id = i.incident_id
SET
  p.employee_id = NULL,
  c.em_address = 'x@x.org',
  c.ad_postal = 'x',
  n.first_name = 'x',
  n.last_name = 'x'
WHERE
  i.confidential_dt IS NOT NULL

What would be the same statement using Oracle 11g?

Thank you!

RTFM

It seems a single query is insufficient when using Oracle:

http://download-west.oracle.com/docs/cd/B10501_01/server.920/a96540/statements_108a.htm#2067717


/** XXX CODING HORROR... */

Depending on your needs, you could use an updateable view. You create a view of your base tables and add an "instead of" trigger to this view and you update the view directly.

Some example tables:

create table party (
    party_id integer,
    employee_id integer
    );

create table party_name (
    party_id integer,
    first_name varchar2(120 char),
    last_name varchar2(120 char)
    );

insert into party values (1,1000);   
insert into party values (2,2000);
insert into party values (3,3000);

insert into party_name values (1,'Kipper','Family');
insert into party_name values (2,'Biff','Family');
insert into party_name values (3,'Chip','Family');

commit;

select * from party_v;

PARTY_ID    EMPLOYEE_ID    FIRST_NAME    LAST_NAME
1            1000           Kipper        Family
2            2000           Biff          Family
3            3000           Chip          Family

... then create an updateable view

create or replace view party_v
as
select
    p.party_id,
    p.employee_id,
    n.first_name,
    n.last_name
from
    party p left join party_name n on p.party_id = n.party_id;

create or replace trigger trg_party_update
instead of update on party_v 
for each row
declare
begin
--
    update party
    set
        party_id = :new.party_id,
        employee_id = :new.employee_id
    where
        party_id = :old.party_id;
--
    update party_name
    set
        party_id = :new.party_id,
        first_name = :new.first_name,
        last_name = :new.last_name
    where
        party_id = :old.party_id;
--
end;
/

You can now update the view directly...

update party_v
set
    employee_id = 42,
    last_name = 'Oxford'
where
    party_id = 1;

select * from party_v;

PARTY_ID    EMPLOYEE_ID    FIRST_NAME    LAST_NAME
1            42             Kipper        Oxford
2            2000           Biff          Family
3            3000           Chip          Family


I was having the same problem I couldn't find a easy way to do this in Oracle.

Look here: Oracle Update Statements for more info.


You could use Oracle MERGE statement to do this. It is a bulk update-or-insert kind of statement based on joining the target table with an inline view.

MERGE INTO bonuses D
   USING (
      SELECT employee_id, salary, department_id FROM employees
      WHERE department_id = 80
   ) S ON (D.employee_id = S.employee_id)
 WHEN MATCHED THEN 
   UPDATE SET D.bonus = D.bonus + S.salary*.01
 WHEN NOT MATCHED THEN 
   INSERT (D.employee_id, D.bonus)
   VALUES (S.employee_id, S.salary*0.1);

if you do not need the insert part, you just omit the last 3 lines above.


In some cases it's possible to use PL/SQL to achieve this. In my case I searched for matching rows in two tables by some criteria, then updated each row in a loop.

Something like this:

begin
  for r in (
    select t1.id as t1_id, t2.id as t2_id
    from t1, t2
    where ...
  ) loop
    update t1
    set ...
    where t1.id = r.t1_id;

    update t2
    set ...
    where t2.id = r.t2_id;
  end loop;
end;
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