I have a code that uses a trigger to do an update into a table after a dml insert has been done, but i need the information inside an atributte that is a nested table, and with that information do the update, but my code throws a mutating table error, and i want to know what is it that i am doing wrong, this is the code with the tables, types and trigger involved.
----create the type tipo_detalle---------------
CREATE OR REPLACE TYPE tipo_detalle AS OBJECT(
codigo NUMBER(1),
cantidad NUMBER(2)
);
/
-----declare the nested table with type tipo_detalle---
CREATE OR REPLACE TYPE detalle_anidado AS TABLE OF tipo_detalle;
/
---------create the table pedido------------------------
CREATE TABLE pedido(
cod_bodega REFERENCES bodega,
dia NUMBER(8),
columna_detalle detalle_anidado,
PRIMARY KEY(cod_bodega,dia)
)
NESTED TABLE columna_detalle STORE AS columna_detalle_anidada
((PRIMARY KEY(NESTED_TABLE_ID,codigo)));
---table where i am going to insert after insert in pedido----
CREATE TABLE inventario(
cod_bodega REFERENCES bodega,
cod_producto REFERENCES producto,
existencia NUMBER(8),
PRIMARY KEY(cod_bodega,cod_producto)
);
------ trigger to do an insert into inventario-----------
CREATE OR REPLACE TRIGGER triggers_de_pedido
FOR INSERT OR UPDATE OR DELETE ON pedido
COMPOUND TRIGGER
contador NUMBER(8);
fila pedido.columna_detalle%TYPE;
cod_producto_ NUMBER(1);
cantidad_ NUMBER(2);
indice NUMBER(4);
AFTER EACH ROW IS
BEGIN
IF INSERTING THEN
SELECT columna_detalle INTO fila FROM pedido WHERE
cod_bodega=:NEW.cod_bodega AND dia=:NEW.dia;
indice:=fila.FIRST;
WHILE indice IS NOT NULL LOOP
cod_producto_:=fila(indice).codigo;
cantidad_:=fila(indice).cantidad;
UPDATE inventario SET existencia=existencia-cantidad_
WHERE cod_bodega=:NEW.cod_bodega AND cod_producto=cod_producto_;
indice:=fila.NEXT(indice);
END LOOP;
END IF;
END AFTER EACH ROW;
END triggers_de_pedido;
/
The error is raised because you are selecting from the Trigger owner(the table pedido) inside the Trigger.
Change this select statement
SELECT columna_detalle INTO fila FROM pedido WHERE ...
to
IF INSERTING THEN
fila := :NEW.columna_detalle;
Related
I got a table Location
CREATE TABLE Location (
idL INTEGER,
City VARCHAR2(15) NOT NULL,
Street VARCHAR2(35) NOT NULL,
Nation CHAR(6) NOT NULL,
CONSTRAINT PK_idL PRIMARY KEY(idL)
);
And a table Person
CREATE TABLE Person(
p_Name VARCHAR2(20) NOT NULL,
p_Surname VARCHAR2(20) NOT NULL,
idP INTEGER,
b_Date DATE NOT NULL,
id_PL INTEGER,
CONSTRAINT PK_idP PRIMARY KEY(idP),
CONSTRAINT FK_idPL FOREIGN KEY(id_PL) REFERENCES Location(idL)
);
I calculate the primary key "automatically" as it follows:
CREATE SEQUENCE seq_loc_pk
start with 1
increment by 1;
CREATE OR REPLACE TRIGGER auto_pk_loc
BEFORE INSERT ON Location
FOR EACH ROW
BEGIN
:new.idL := seq_loc_pk.nextval;
END;
/
Now I want to insert the residence for a new person (after I've created the right view of course) with an instead of trigger like this:
CREATE OR REPLACE TRIGGER newperson
INSTEAD OF INSERT ON Residence
FOR EACH ROW
DECLARE
nl Loc.idL%TYPE;
BEGIN
ALTER TRIGGER auto_pk_loc DISABLE; -- Error
nl := seq_loc_pk.nextval;
:NEW.idL := nl;
INSERT INTO Location VALUES(:NEW.City,:NEW.Street,:NEW.Nation);
INSERT INTO Patient VALUES(:NEW.P_Name,:NEW.P_Surname,:NEW.B_Date,,nl);
ALTER TRIGGER auto_pk_loc ENABLE;
END;
/
I thought about disabling and enabling the trigger auto_pk_loc so that it doesn't create extra values for no reason, but I think this is not the right way to do it? What is it though? Thanks for whoever answers.
You can do this by placing it in execute immedaite:
BEGIN
execute immedidate 'ALTER TRIGGER auto_pk_loc DISABLE';
nl := seq_loc_pk.nextval;
:NEW.idL := nl;
INSERT INTO Location VALUES(:NEW.City,:NEW.Street,:NEW.Nation);
INSERT INTO Patient VALUES(:NEW.P_Name,:NEW.P_Surname,:NEW.B_Date,,nl);
execute immedidate 'ALTER TRIGGER auto_pk_loc ENABLE';
END;
/
But this will cause you all sorts of issues; DDL commits so you'll have to make this an autonomous transaction and you'll hit concurrency problems. This is best avoided.
A better method is to use the returning clause to fetch the value you just inserted:
BEGIN
INSERT INTO Location VALUES(:NEW.City,:NEW.Street,:NEW.Nation)
returning idl into nl;
INSERT INTO Patient VALUES(:NEW.P_Name,:NEW.P_Surname,:NEW.B_Date,nl);
END;
/
Though as #astentx noted, you probably want to use merge to avoid having duplicate locations. This doesn't support returing, so you'll have to use some combination of insert+update instead.
Finally - assuming you're on 12c or higher - it's better to use an identity column or sequence default to auto-generate the location IDs over a trigger.
I have 2 simple tables:
CREATE TABLE ORDERS
( ORDER_KEY number(10) NOT NULL,
ORDER_NR varchar2(50) NOT NULL,
LAST_UPDATE DATE,
CONSTRAINT ORDERS_PK PRIMARY KEY (ORDER_KEY)
);
CREATE TABLE ORDER_POSITIONS
( ORDER_POS_KEY number(10) NOT NULL,
ORDER_POS_NR number(10),
ORDER_POS_DESCRIPTION varchar2(50),
ORDER_KEY NUMBER(10) NOT NULL,
CONSTRAINT ORDER_POSITIONS_PK PRIMARY KEY (ORDER_POS_KEY),
CONSTRAINT ORDERS_FK
FOREIGN KEY (ORDER_KEY)
REFERENCES ORDERS(ORDER_KEY)
ON DELETE CASCADE
);
On the table ORDER_POSITIONS I created a trigger which should update the column LAST_UPDATE whenever a position is deleted.
CREATE OR REPLACE TRIGGER TGAUDIT_ORDER_POS
AFTER DELETE
ON ORDER_POSITIONS
FOR EACH ROW
DECLARE
BEGIN
UPDATE ORDERS O SET O.LAST_UPDATE = SYSDATE WHERE O.ORDER_KEY = :OLD.ORDER_KEY;
END;
If I delete a position from the table ORDER_POSITION, everything is working fine (the column LAST_UPDATE is updated).
However, if I want to delete an order, all its positions are gonna be deleted, too (via CASCADE DELETE). At this moment also the trigger on the table ORDER_POSITIONS is being raised and it wants to update the column of the table which is currently being deleted - ORDERS. Obviously I get here the error : ORA-04091 Table ORDERS is mutating.
Is there a way to get it solved?
I solved it finally using a compound trigger:
CREATE OR REPLACE TRIGGER TGAUDIT_ORDER_POS
FOR DELETE ON ORDER_POSITIONS
COMPOUND TRIGGER
TYPE parent_key_type IS TABLE OF ORDERS.ORDER_KEY%TYPE;
parent_keys parent_key_type := parent_key_type();
AFTER EACH ROW IS BEGIN
IF DELETING THEN
BEGIN
parent_keys.extend;
parent_keys(parent_keys.last) := :old.ORDER_KEY;
END;
END IF;
END AFTER EACH ROW;
AFTER STATEMENT IS BEGIN
FOR i IN 1..parent_keys.count LOOP
UPDATE DEVART_TEST.ORDERS O SET O.LAST_UPDATE = SYSDATE WHERE O.ORDER_KEY = parent_keys(i);
END LOOP;
END AFTER STATEMENT;
END;
UPDATE: Another option would be to catch this specific exception within the regular trigger.
CREATE OR REPLACE TRIGGER TGAUDIT_ORDER_POS
AFTER DELETE
ON ORDER_POSITIONS
FOR EACH ROW
DECLARE
TABLE_MUTATING EXCEPTION;
PRAGMA EXCEPTION_INIT(TABLE_MUTATING, -4091 );
BEGIN
UPDATE ORDERS O SET O.LAST_UPDATE = SYSDATE WHERE O.ORDER_KEY = :OLD.ORDER_KEY;
EXCEPTION
WHEN TABLE_MUTATING THEN
NULL; -- suppress
END;
I would recreate the foreign-key constraint without the ON DELETE CASCADE clause and delete all order positions before deleting an order. That way you avoid the mutating table error by not having two tables mutating at the same time.
so the problem is I have two tables and before inserting or updating the values on one table I have to check if the other table does not contain the new value I'm trying to insert/update like so:
CREATE TABLE categoriasimples(
nome varchar(64) PRIMARY KEY REFERENCES categoria(nome) ON DELETE CASCADE);
CREATE TABLE supercategoria(
nome varchar(64) PRIMARY KEY REFERENCES categoria(nome) ON DELETE CASCADE);
CREATE FUNCTION check_categoria_type_sup() RETURNS trigger AS $check_categoria_type_sup$
BEGIN
IF nome FROM categoriasimples WHERE (NEW.nome = CategoriaSimples.nome) IS NOT NULL THEN
RAISE EXCEPTION 'Uma categoria nao pode ser super e simples ao mesmo tempo!';
END IF;
RETURN NEW;
END;
$check_categoria_type_sup$ LANGUAGE plpgsql;
CREATE TRIGGER check_categoria_type_sup BEFORE INSERT OR UPDATE ON supercategoria FOR EACH ROW EXECUTE PROCEDURE check_categoria_type_sup();
CREATE FUNCTION check_categoria_type_simp() RETURNS trigger AS $check_categoria_type_simp$
BEGIN
IF nome FROM supercategoria WHERE (supercategoria.nome = NEW.nome) IS NOT NULL THEN
RAISE EXCEPTION 'Uma categoria nao pode ser simples e super ao mesmo tempo!';
END IF;
RETURN NEW;
END;
$check_categoria_type_simp$ LANGUAGE plpgsql;
CREATE TRIGGER check_categoria_type_simp BEFORE INSERT OR UPDATE ON categoriasimples FOR EACH ROW EXECUTE PROCEDURE check_categoria_type_simp();
I can insert values into one table but if I try to insert in the other table it says:
ERROR: invalid input syntax for type boolean: "bife" (Value that was in the other table)
CONTEXT: PL/pgSQL function check_categoria_type_sup() line 3 at IF
SQL state: 22P02
This is too long for a comment.
I'm pretty sure you can do what you want without using triggers. I would suggest that you investigate inheritance, which Postgres supports for tables.
You can just define a unique constraint on the parent table and not have to worry about trying to get two different tables to be in sync.
I am a beginner of SQL and Oracle database, and I need a little help about trigger. Here is the question:
I need to create a trigger that before insert a row into table Room, it will check this new row's hotel_id to see if it exists in another table Hotel. If the new hotel_id exists, then do the insert; if not, cancel this insert.
My code:
CREATE OR REPLACE TRIGGER TRIGGER1
BEFORE INSERT ON ROOM
FOR EACH ROW
BEGIN
if (:new.hotel_id in (select hotel_id from hotel)) then
--execute the insert;
else
--cancel the insert;
end if;
END;
I'm not sure that SQL has syntax that can be used to continue or cancel an operation. If there is, please teach me or attach the link related to it.
Correct way of doing this is using foreign key constraints.
You can define/alter your room table to refer it in the hotel_id column.
CREATE TABLE:
create table room (
. . .,
hotel_id int not null,
constraint fk_hotel_id foreign key (hotel_id)
references hotel(hotel_id)
);
ALTER TABLE:
alter table room
add constraint fk_hotel_id foreign key (hotel_id)
references hotel(hotel_id);
If the two table exists in different databases, then you can use trigger.
You can use raise_application_error proc to abort the execution and throw error.
create or replace trigger trigger1
before insert or update
on room for each row
declare
n integer := 0;
begin
select count(*) into n
from hotel
where hotel_id = :new.hotel_id;
if n = 0 then
raise_application_error(-20001, 'Hotel ID doesn't exist');
end if;
end;
As GurV said, foreign keys are more appropriate way for doing this
Though, here is trigger way:
CREATE OR REPLACE TRIGGER TRIGGER1
BEFORE INSERT ON ROOM
FOR EACH ROW
declare myvar INT;
BEGIN
SELECT 1 INTO myvar FROM Hotel WHERE hotel_id = :NEW.hotel_id FETCH NEXT 1 ROW ONLY;
exception
when no_data_found then
RAISE_APPLICATION_ERROR (-20000, 'some_error_message');
END;
I need some assistance with troubleshooting the trigger that I'm trying to create/use for logging updates and inserts on a table.
I'm using a customers_history table to track all the changes being made on the customers table.
CREATE TABLE customers (
custID INTEGER PRIMARY KEY,
custFName VARCHAR2(30),
custLName VARCHAR2(30),
custState CHAR(20),
custZip NUMBER(5)
);
-- log inserts and updates on customers table
CREATE TABLE customers_history (
histID INTEGER PRIMARY KEY,
cID INTEGER,
cFName VARCHAR2(30),
cLName VARCHAR2(30),
cState CHAR(20),
cZip NUMBER(5)
);
Also, for the histID I'm using a sequence to auto increment the histID on customers_history table.
CREATE SEQUENCE ch_seq
MINVALUE 1
START WITH 1
INCREMENT BY 1;
CREATE OR REPLACE TRIGGER audit_customers
BEFORE UPDATE
OR INSERT ON customers
FOR EACH ROW
BEGIN
INSERT INTO customers_history(histID,cID,cFName,cLName,cState,cZip)
VALUES(ch_seq.nextval,:NEW.custID,:NEW.custFName,:NEW.custLName,
:NEW.custState,:NEW.custZip);
END;
/
I have been inserting two rows on customers prior to creating the trigger, and they work fine. After I create the trigger, it will not allow me to insert anymore rows on customers and it also throws the ORA-04098: trigger 'SYSTEM.AUDIT_CUSTOMERS' is invalid and failed re-validation 04098. 00000 - "trigger '%s.%s' is invalid and failed re-validation" error message.
I've tried to see if there is any code errors using select * from user_errors where type = 'TRIGGER' and name = 'audit_customers'; and it returned no lines. Not sure if that helps or not. Thanks.
you have created your trigger for multiple DML operations (Insert and Update) so you need to specipy the DML operation by using IF INSERTING THEN....END IF; and IF UPDATING THEN....END IF; for example:
CREATE OR REPLACE TRIGGER audit_customers
BEFORE UPDATE
OR INSERT ON customers
FOR EACH ROW
BEGIN
IF INSERTING THEN
INSERT INTO customers_history(histID,cID,cFName,cLName,cState,cZip)
VALUES(ch_seq.nextval,:NEW.custID,:NEW.custFName,:NEW.custLName,
:NEW.custState,:NEW.custZip);
END IF;
END;
/
I went through and changed a couple things and it seems to work for both insert and update operations. I dropped the tables, sequence, and trigger, then did the tried the following code and it works now. Thank you all for your time and inputs!
CREATE TABLE customers (
custID INTEGER,
custFName VARCHAR2(30),
custLName VARCHAR2(30),
custState CHAR(20),
custZip NUMBER(5)
);
CREATE TABLE customers_history (
histID INTEGER,
cID INTEGER,
cFName VARCHAR2(30),
cLName VARCHAR2(30),
cState CHAR(20),
cZip NUMBER(5)
);
CREATE OR REPLACE TRIGGER audit_customers
BEFORE UPDATE
OR INSERT ON customers
FOR EACH ROW
BEGIN
INSERT INTO customers_history(
histID,
cID,
cFName,
cLName,
cState,
cZip
)
VALUES(
ch_seq.nextval,
:new.custID,
:new.custFName,
:new.custLName,
:new.custState,
:new.custZip
);
END;
/
I used the same sequence code as before, added a couple of rows, and it worked. Then I altered the two tables, by adding the primary keys,
ALTER TABLE customers ADD PRIMARY KEY(custID);
ALTER TABLE customers_history ADD PRIMARY KEY(histID);
inserted a couple other columns, modified a few rows, and it still worked. I'm a happy camper, although I'm not certain what or how it actually got fixed.