Inserting multiple records from a trigger in oracle - oracle

i created a trigger to insert the employeeIDs whenever a position is updated.
In some cases, there are many employees attached to one position so the trigger isnt able to insert all the employees (only 1). i need all the employee Ids
can any1 help me with this code?
Regards
create or replace trigger postn_updt
after update on postn
for each row
declare
cursor m is
select u.login
from user u,
party_per s
where u.row_id=s.person_id
and s.party_id=:new.row_id;
rownum varchar2(10);
begin
if updating ('postn_type_cd') then
open mult;
fetch mult into rownum;
insert into test123
(employee_number,type,request_date,remarks)
values
(( rownum,
'Updated',sysdate,''
);
close m;
end if;
end;

Triggers != Application code
If you embed application code in trigger like this then it will be horrible to maintain and debug and you'll always be encountering situations where a trigger-based approach won't work because of a mutating table error.
You would do much better to keep triggers for only auditing and other non-application activities, and put this kind of logic in the application itself.

to insert multiple rows you will need either a LOOP or some form of "INSERT... SELECT" statement.
eg.
create or replace trigger postn_updt
after update on postn
for each row
declare
cursor m is
select u.login
from user u,
party_per s
where u.row_id=s.person_id
and s.party_id=:new.row_id;
begin
if updating ('postn_type_cd') then
for mult_rec in m LOOP
insert into test123
(employee_number,type,request_date,remarks)
values
(( mult_rec.login,
'Updated',sysdate,''
);
END LOOP;
end if;
end;
OR
create or replace trigger postn_updt
after update on postn
for each row
declare
begin
if updating ('postn_type_cd') then
insert into test123
(employee_number,type,request_date,remarks)
select u.login ,'Updated',sysdate,''
from user u,
party_per s
where u.row_id=s.person_id
and s.party_id=:new.row_id;
end if;
end;

Related

How to rollback a column and its trigger in plsql?

I have a litte task. Firstly I added a column in my table with specific constraints. Then I added a trigger for other jobs.
But I need a rollbacksql and have no idea what to proceed. Can anybody help or give an advice about it? I am adding my sql snippet.
ALTER TABLE FCBSADM.GL_DEF ADD GL_TP NUMBER;
ALTER TABLE FCBSADM.GL_DEF ADD CONSTRAINTS CH_COL CHECK (GL_TP between 1 and 10);
CREATE OR REPLACE TRIGGER GL_DEF_GL_TP_TRG
BEFORE INSERT OR
DELETE OR
UPDATE OF CDATE, CMPNY_DEF_ID, CUSER, DESCR, GL_DEF_ID, MNY_TP_ID, ST, UDATE, UUSER, GL_TP
ON FCBSADM.GL_DEF
FOR EACH ROW
DECLARE
cnt number := 0;
BEGIN
IF INSERTING
THEN
IF :NEW.GL_TP = 2
THEN
SELECT 1 into cnt from dual where exists( select *
FROM LOOKUP_GLCODE_IND_CEZA lookup
WHERE lookup.indirim_glcode = :NEW.gl_Def_id);
IF (cnt = 1) THEN
raise_application_error
(-20101, 'Please insert record into LOOKUP_GLCODE_IND_CEZA before inserting GL_DEF');
END IF;
END IF;
END IF;
END;
What do you want to rollback? Adding a column and creating a trigger? If so, drop them, both.
alter table gl_def drop column gl_tp;
drop trigger gl_def_gl_tp_trg;
A trigger and newly added table can be rolled back only by using drop and alter statements. This is ok if its being done inside a script that executes only a few times. But is highly inefficient if both drop and alter are called frequently for n number of records.

Statement level trigger to enforce a constraint

I am trying to implement a statement level trigger to enforce the following "An applicant cannot apply for more than two positions in one day".
I am able to enforce it using a row level trigger (as shown below) but I have no clue how to do so using a statement level trigger when I can't use :NEW or :OLD.
I know there are alternatives to using a trigger but I am revising for my exam that would have a similar question so I would appreciate any help.
CREATE TABLE APPLIES(
anumber NUMBER(6) NOT NULL, /* applicant number */
pnumber NUMBER(8) NOT NULL, /* position number */
appDate DATE NOT NULL, /* application date*/
CONSTRAINT APPLIES_pkey PRIMARY KEY(anumber, pnumber)
);
CREATE OR REPLACE TRIGGER app_trigger
BEFORE INSERT ON APPLIES
FOR EACH ROW
DECLARE
counter NUMBER;
BEGIN
SELECT COUNT(*) INTO counter
FROM APPLIES
WHERE anumber = :NEW.anumber
AND to_char(appDate, 'DD-MON-YYYY') = to_char(:NEW.appDate, 'DD-MON-YYYY');
IF counter = 2 THEN
RAISE_APPLICATION_ERROR(-20001, 'error msg');
END IF;
END;
You're correct that you don't have :OLD and :NEW values - so you need to check the entire table to see if the condition (let's not call it a "constraint", as that term has specific meaning in the sense of a relational database) has been violated:
CREATE OR REPLACE TRIGGER APPLIES_AIU
AFTER INSERT OR UPDATE ON APPLIES
BEGIN
FOR aRow IN (SELECT ANUMBER,
TRUNC(APPDATE) AS APPDATE,
COUNT(*) AS APPLICATION_COUNT
FROM APPLIES
GROUP BY ANUMBER, TRUNC(APPDATE)
HAVING COUNT(*) > 2)
LOOP
-- If we get to here it means we have at least one user who has applied
-- for more than two jobs in a single day.
RAISE_APPLICATION_ERROR(-20002, 'Applicant ' || aRow.ANUMBER ||
' applied for ' || aRow.APPLICATION_COUNT ||
' jobs on ' ||
TO_CHAR(aRow.APPDATE, 'DD-MON-YYYY'));
END LOOP;
END APPLIES_AIU;
It's a good idea to add an index to support this query so it will run efficiently:
CREATE INDEX APPLIES_BIU_INDEX
ON APPLIES(ANUMBER, TRUNC(APPDATE));
dbfiddle here
Best of luck.
Your rule involves more than one row at the same time. So you cannot use a FOR ROW LEVEL trigger: querying on APPLIES as you propose would hurl ORA-04091: table is mutating exception.
So, AFTER statement it is.
CREATE OR REPLACE TRIGGER app_trigger
AFTER INSERT OR UPDATE ON APPLIES
DECLARE
cursor c_cnt is
SELECT 1 INTO counter
FROM APPLIES
group by anumber, trunc(appDate) having count(*) > 2;
dummy number;
BEGIN
open c_cnt;
fetch c_cnt in dummy;
if c_cnt%found then
close c_cnt;
RAISE_APPLICATION_ERROR(-20001, 'error msg');
end if;
close c_cnt;
END;
Obviously, querying the whole table will be inefficient at scale. (One of the reasons why triggers are not recommended for this sort of thing). So this is a situation in which we might want to use a compound trigger (assuming we're on 11g or later).

PL/SQL ORACLE triggers

I'm trying to create a trigger that when you insert an employee in the company, assign a commission of 0.10 if it is from department 80. This is what I've tried so far:
CREATE OR REPLACE TRIGGER emp_com
BEFORE INSERT ON employees
FOR EACH ROW
WHEN (NEW.DEPARTMENT_ID= '80')
BEGIN
IF INSERTING THEN
:NEW.commission_pct := 0.10;
END IF;
END;
Your trigger should work fine in its current state; however, the "IF INSERTING" bit is redundant since your trigger only fires for inserts anyway.
CREATE OR REPLACE TRIGGER emp_com
BEFORE INSERT ON employees
FOR EACH ROW
WHEN (NEW.DEPARTMENT_ID= '80')
BEGIN
:NEW.commission_pct := 0.10;
END;

trigger after insert on table

create or replace
trigger addpagamento
after insert on marcacoes_refeicoes
for each row
declare
nmarcacaoa number;
ncartaoa number;
begin
select nmarcacao into nmarcacaoa from marcacoes_refeicoes where rownum < (select count(*) from marcacoes_refeicoes);
select ncartao into ncartaoa from marcacoes_refeicoes where rownum < (select count(*) from marcacoes_refeicoes);
insert_pagamentos(nmarcacaoa, ncartaoa); --this is a procedure
exception when others then
raise_application_error(-20001, 'Error in Trigger!!!');
end addpagamento;
when i try to run the insert statement to the table "marcacoes_refeicoes" this procedure gives error: like the table is mutating
create or replace
procedure insert_pagamentos
(nmarcacaoa in number, ncartaoa in number)
AS
BEGIN
insert into pagamentos (nmarcacao, datapagamento, ncartao) values (nmarcacaoa, sysdate, ncartaoa);
commit;
END INSERT_PAGAMENTOS;
Short (oversimplified) answer:
You can't modify a table in a trigger that changes the table.
Long answer:
http://www.oracle-base.com/articles/9i/mutating-table-exceptions.php has a more in-depth explanation, including suggestions how to work around the problem.
You're hitting the mutating-table problem because you're selecting from the same table the trigger is on, but what you seem to be trying to do doesn't make sense. Your queries to get a value for nmarcacaoa and ncartaoa will return a no_data_found or too_many_rows error unless the table had exactly 2 rows in it before your insert:
select nmarcacao from marcacoes_refeicoes
where rownum < (select count(*) from marcacoes_refeicoes);
will return all rows except one; and the one that's excluded will be kind of random as you have no ordering. Though the state is undetermined within the trigger, so you can't really how many rows there are, and it won't let you do this query anyway. You won't normally be able to get a single value, anyway, and it's not obvious which value you actually want.
I can only imagine that you're trying to use the values from the row you are currently inserting, and putting them in your separate payments (pagamentos) table. If so there is a built-in mechanism to do that using correlation names, which lets you refer to the newly inserted row as :new (by default):
create or replace
trigger addpagamento
after insert on marcacoes_refeicoes
for each row
begin
insert_pagamentos(:new.nmarcacaoa, :new.ncartaoa);
end addpagamento;
The :new is referring to the current row, so :new.nmarcacaoa is the nmarcacaoa being inserted. You don't need to (and can't) get that value from the table itself. (Even with the suggested autonomous pragma, that would be a separate transaction and would not be able to see your newly inserted and uncommitted data).
Or you can just do the insert directly; not sure what the procedure is adding here really:
create or replace
trigger addpagamento
after insert on marcacoes_refeicoes
for each row
begin
insert into pagamentos(nmarcacao, datapagamento, ncartao)
values (:new.nmarcacaoa, sysdate, :new.ncartaoa);
end addpagamento;
I've removed the exception handler as all it was doing was masking the real error, which is rather unhelpful.
Editing this answer in view of the comments below:
You can use PRAGMA AUTONOMOUS_TRANSACTION to get rid of the error, but DONOT USE it as it will NOT solve any purpose.
Use PRAGMA AUTONOMOUS_TRANSACTION:
create or replace
trigger addpagamento
after insert on marcacoes_refeicoes
for each row
declare
PRAGMA AUTONOMOUS_TRANSACTION;
nmarcacaoa number;
ncartaoa number;
begin
select nmarcacao into nmarcacaoa from marcacoes_refeicoes where rownum < (select count(*) from marcacoes_refeicoes);
select ncartao into ncartaoa from marcacoes_refeicoes where rownum < (select count(*) from marcacoes_refeicoes);
insert_pagamentos(nmarcacaoa, ncartaoa); --this is a procedure
exception when others then
raise_application_error(-20001, 'Error in Trigger!!!');
end addpagamento;
However in this case , select count(*) from marcacoes_refeicoes will give you the new count after the current insertion into the table.

Simple oracle insert

I am trying to simply insert some information to a table in Oracle using Forms. Sometimes the insert statement works, sometimes it doesn't. I'm just not experienced enough with Oracle to understand what's not working. Here's the code:
PROCEDURE create_account IS
temp_name varchar2(30);
temp_street varchar2(30);
temp_zip number(5);
temp_phone varchar2(30);
temp_login passuse.login%type;
temp_pass varchar2(30);
temp_total number(4);
temp_lgn passuse.lgn%type;
cursor num_cursor is
select MAX(ano)
from accounts;
cursor lgn_cursor is
select MAX(lgn)
from passuse;
BEGIN
temp_name:= Get_Item_Property('ACCOUNTS.A_NAME', database_value);
temp_street:= Get_Item_Property('ACCOUNTS.STREET', database_value);
temp_zip:= Get_Item_Property('ACCOUNTS.ZIP', database_value);
temp_phone:= Get_Item_Property('ACCOUNTS.STREET', database_value);
temp_login:= Get_Item_Property('PASSUSE.LOGIN', database_value);
temp_pass:= Get_Item_Property('PASSUSE.PASS', database_value);
open num_cursor;
fetch num_cursor into temp_total;
open lgn_cursor;
fetch lgn_cursor into temp_lgn;
if(lgn_cursor%found) then
if(num_cursor%found) then
temp_lgn := temp_lgn + 20;
--the trouble maker..
INSERT INTO passuse (lgn, a_type, login, pass)
VALUES (temp_lgn, 1, temp_login, temp_pass);
temp_total := temp_total+1;
INSERT INTO accounts(ano,lgn,a_name,street,zip,phone)
VALUES (temp_total,temp_lgn,temp_name,temp_street,temp_zip,temp_phone);
end if;
end if;
close lgn_cursor;
close num_cursor;
commit;
END;
To expand on #Mikpa's comment - it certainly appears that getting the values for ACCOUNTS.ANO and PASSUSE.LGN from sequences would be a good idea. Populating these fields automatically by using a trigger would also be helpful. Something like the following:
-- Note that the following is intended as a demo. When executing these statements
-- you'll probably have to modify them for your particular circumstances.
SELECT MAX(ANO) INTO nMax_ano FROM ACCOUNTS;
SELECT MAX(LGN) INTO nMax_lgn FROM PASSUSE;
CREATE SEQUENCE ACCOUNTS_SEQ START WITH nMax_ano+1;
CREATE SEQUENCE PASSUSE_SEQ START WITH nMax_lgn+1;
CREATE TRIGGER ACCOUNTS_BI
BEFORE INSERT ON ACCOUNTS
FOR EACH ROW
BEGIN
SELECT ACCOUNTS_SEQ.NEXTVAL
INTO :NEW.ANO
FROM DUAL;
END ACCOUNTS_BI;
CREATE TRIGGER PASSUSE_BI
BEFORE INSERT ON PASSUSE
FOR EACH ROW
BEGIN
SELECT PASSUSE_SEQ.NEXTVAL
INTO :NEW.LGN
FROM DUAL;
END PASSUSE_BI;
Having done the above you can now write your inserts into these tables as
INSERT INTO passuse (a_type, login, pass)
VALUES (1, temp_login, temp_pass)
RETURNING LGN INTO temp_lgn;
and
INSERT INTO accounts(lgn, a_name, street, zip, phone)
VALUES (temp_lgn, temp_name, temp_street, temp_zip, temp_phone);
Note that in the both statements the key values (PASSUSE.LGN and ACCOUNTS.ANO) are not mentioned in the field list as the new triggers should take care of filling them in correctly. Also note that when inserting into PASSUSE the RETURNING clause is used to get back the new value for LGN so it can be used in the insert into the ACCOUNTS table.
Share and enjoy.

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