Oracle PL/SQL: Forwarding whole row to procedure from a trigger
In have an Oracle (10i) PL/SQL Row-Level trigger which is responsible for three independent tasks. As the trigger is relatively cluttered that way, I want to export these three tasks into three stored procedures.
I was thinking of using a my_table%ROWTYPE
parameter or maybe a collection type for the procedures, but my main concern is how to fill t开发者_StackOverflowhese parameters.
Is there a way to put the whole :NEW
row of a trigger into a single variable easily?
So far the only way I could find out was assigning each field separately to the variable which is not quite satisfying, looking at code maintenance etc.
Something like
SELECT :NEW.* INTO <variable> FROM dual;
would be preferred. (I haven't tried that actually but I suppose it wouldn't work)
In the vast majority of cases, the only way to assign the new values in the row to a %ROWTYPE variable would be to explicitly assign each column. Something like
CREATE OR REPLACE TRIGGER some_trigger_name
BEFORE INSERT OR UPDATE ON some_table
FOR EACH ROW
DECLARE
l_row some_table%rowtype;
BEGIN
l_row.column1 := :NEW.column1;
l_row.column2 := :NEW.column2;
...
l_row.columnN := :NEW.columnN;
procedure1( l_row );
procedure2( l_row );
procedure3( l_row );
END;
If your table happens to be declared based on an object, :NEW will be an object of that type. So if you have a table like
CREATE OR REPLACE TYPE obj_foo
AS OBJECT (
column1 NUMBER,
column2 NUMBER,
...
columnN NUMBER );
CREATE TABLE foo OF obj_foo;
then you could declare procedures that accept input parameters of type OBJ_FOO
and call those directly from your trigger.
The suggestion in the other thread about selecting the row from the table in an AFTER INSERT/ UPDATE thread, unfortunately, does not generally work. That will generally lead to a mutating table exception.
1 create table foo (
2 col1 number,
3 col2 number
4* )
SQL> /
Table created.
SQL> create procedure foo_proc( p_foo in foo%rowtype )
2 as
3 begin
4 dbms_output.put_line( 'In foo_proc' );
5 end;
6 /
Procedure created.
SQL> create or replace trigger trg_foo
2 after insert or update on foo
3 for each row
4 declare
5 l_row foo%rowtype;
6 begin
7 select *
8 into l_row
9 from foo
10 where col1 = :new.col1;
11 foo_proc( l_row );
12 end;
13 /
Trigger created.
SQL> insert into foo values( 1, 2 );
insert into foo values( 1, 2 )
*
ERROR at line 1:
ORA-04091: table SCOTT.FOO is mutating, trigger/function may not see it
ORA-06512: at "SCOTT.TRG_FOO", line 4
ORA-04088: error during execution of trigger 'SCOTT.TRG_FOO'
It's not possible that way.
Maybe my answer to another question can help.
Use SQL to generate the SQL;
select ' row_field.'||COLUMN_NAME||' := :new.'||COLUMN_NAME||';' from
ALL_TAB_COLUMNS cols
where
cols.TABLE_NAME = 'yourTableName'
order by cols.column_name
Then copy and paste output.
This is similar to Justins solution but a little bit shorter (no typing of left part of each assignment) :
-- use instead of the assignments in Justins example:
select :new.column1,
:new.column2,
...
:new.columnN,
into l_row from dual;
精彩评论