Update trigger not updating timestamp(update operation) in column - sql

Question

Trigger not working while updating the table column with trigger enabled on table...
CREATE OR REPLACE Trigger TR_FinlStatAssetDesignation_U
BEFORE Update
on FINLSTATASSETDESIGNATION FOR EACH ROW
DECLARE
v_AtDateTime TIMESTAMP(3);
v_LogOperation NUMBER(3,0);
v_UserName VARCHAR2(255);
v_AppName VARCHAR2(255);
SWV_error NUMBER(10,0) DEFAULT 0;
BEGIN
begin
select USERNAME INTO v_UserName FROM v$session WHERE (audsid = SYS_CONTEXT('userenv','sessionid')) AND ROWNUM <=1;
EXCEPTION
WHEN NO_DATA_FOUND THEN
NULL;
end;
SELECT program INTO v_AppName FROM v$session WHERE audsid=userenv('sessionid');
if (LENGTH(v_AppName) = 0) then
v_AppName := 'Unknown';
end if;
SELECT distinct TO_CHAR(SYSTIMESTAMP,'DD-MON-YY hh24:mi:SS.FF AM') INTO v_AtDateTime FROM dual;
if UPDATING('FinlStatAssetDesignation') then
RAISE_APPLICATION_ERROR(-20000,'Invalid attempt to update OID FinlStatAssetDesignation in FinlStatAssetDesignation');
/*
ROLLBACK */
return;
end if;
if not UPDATING('UpdDate') then
SWV_error := 0;
begin
UPDATE FinlStatAssetDesignation a SET(UpdDate) =(SELECT distinct v_AtDateTime FROM dual where a.FinlStatAssetDesignation = :NEW.FinlStatAssetDesignation)
WHERE ROWID IN(SELECT a.ROWID FROM FinlStatAssetDesignation a where a.FinlStatAssetDesignation = :NEW.FinlStatAssetDesignation);
EXCEPTION
WHEN OTHERS THEN
SWV_error := SQLCODE;
end;
if SWV_error <> 0 then
/*
ROLLBACK */
return;
end if;
end if;
END;
QL> select * from finlstatassetdesignation;
FINLSTATAS FINLSTATASSETDESIGNATIONDESC UPDOPERATION
---------- -------------------------------------------------- ------------
UPDDATE
---------------------------------------------------------------------------
one19 anything 0
01-JAN-17 08.00.00.000000 AM
SQL> update finlstatassetdesignation set finlstatassetdesignationdesc ='nothing';
1 row updated.
SQL> select * from finlstatassetdesignation;
FINLSTATAS FINLSTATASSETDESIGNATIONDESC UPDOPERATION
---------- -------------------------------------------------- ------------
UPDDATE
---------------------------------------------------------------------------
one19 nothing 0
01-JAN-17 08.00.00.000000 AM
SQL> desc finlstatassetdesignation;
Name Null? Type
----------------------------------------- -------- ----------------------------
FINLSTATASSETDESIGNATION NOT NULL CHAR(10 CHAR)
FINLSTATASSETDESIGNATIONDESC NOT NULL VARCHAR2(50 CHAR)
UPDOPERATION NOT NULL NUMBER(10)
UPDDATE NOT NULL TIMESTAMP(6)
Trying to update column FINLSTATASSETDESIGNATIONDESC gets succeded however doesnt update the timestamp in column UPDDATE
Please help....in fixing this trigger...
Trigger not working while updating the table column with trigger enabled on table...

Answer 1

Usually it is a bad idea to write strings (i.e. TO_CHAR(SYSTIMESTAMP,'DD-MM-YY hh24:mi:SS.FF AM') INTO v_AtDateTime) when you actually want to write timestamps.
There are several weak points in your code, according to my understanding you can write it simpler:
CREATE OR REPLACE TRIGGER TR_FinlStatAssetDesignation_U
BEFORE UPDATE
ON FINLSTATASSETDESIGNATION FOR EACH ROW
BEGIN
IF UPDATING('FinlStatAssetDesignation') THEN
RAISE_APPLICATION_ERROR(-20000,'Invalid attempt to update OID FinlStatAssetDesignation in FinlStatAssetDesignation');
-- Rather strange if a column has the same name as the table
END IF;
IF NOT UPDATING('UpdDate') THEN
:NEW.UpdDate := SYSTIMESTAMP;
END IF;
END;
Everything else in your code is redundant, resp. junk.
In case you need the username somewhere, just write USER instead of
select USERNAME INTO v_UserName
FROM v$session
WHERE (audsid = SYS_CONTEXT('userenv','sessionid')) AND ROWNUM <=1;
For application use NVL(SYS_CONTEXT('USERENV', 'CLIENT_PROGRAM_NAME'), 'Unknown') instead of
SELECT program INTO v_AppName FROM v$session WHERE audsid=userenv('sessionid');
if (LENGTH(v_AppName) = 0) then
v_AppName := 'Unknown';
end if;