Triggers en Oracle (campos autoincrementables)

Adriana Gómez — Tue, 30 Nov 2021 16:51:02 +0000

Creación de una tabla Primero, debemos tener la tabla con los campos para poder crear su trigger más adelante. Para crear la tabla, lo hacemos desde la interfaz o bien, de la siguiente manera con comandos:

CREATE TABLE Animales (id_animal number primary key, nombre VARCHAR2(25) NOT NULL, color VARCHAR2(25) NOT NULL);

Creación de una secuencia Una vez la tabla esté lista, le indicamos con una secuencia, que inicie en 1 y se incremente en 1 cada vez que se vaya a insertar un dato:

CREATE SEQUENCE canimales START WITH 1 INCREMENT BY 1;

Creación del trigger Para que el campo 'id_animal' se autoincremente de una manera elegante, utilizaremos el trigger para que se encargue de obtener e insertar el valor de la secuencia automáticamente. La manera correcta de crear uno, es la siguiente:

CREATE TRIGGER TRIG_ANIMALES BEFORE INSERT ON Animales FOR EACH ROW BEGIN SELECT canimales.NEXTVAL INTO :NEW.id_animal FROM DUAL; END;

Este trigger lo podemos encontrar en la carpeta 'Disparadores' de las propiedades de la tabla:

Inserción de datos Listo, ahora podemos insertar datos y cada uno tendrá un id único gracias al trigger:

INSERT INTO Animales (nombre, color) VALUES ('Caballo', 'Blanco');

How to install Oracle 18c and Docker on Ubuntu 20

Adriana Gómez — Sat, 23 Oct 2021 20:43:53 +0000

First Step: installing docker on ubuntu

Update your existing package list: $ sudo apt update
Next, install some prerequisite packages that allow apt to use packages over HTTPS: $ sudo apt install apt-transport-https ca-certificates curl software-properties-common
Then, add the GPG key for the official Docker repository on your system: $ curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
Add the Docker repository to the APT feeds: $ sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu focal stable"
Next, update the database package with the Docker packages from the newly added repository: $ sudo apt update
Make sure you're about to install from the Docker repository instead of the default Ubuntu repository: $ apt-cache policy docker-ce While the Docker version number may be different, you will see an output like this
Finally, install Docker: $ sudo apt install docker-ce
Check that it works: $ sudo systemctl status docker the output will show that the service is active and running :)

Second Step: installing oracle 18c on docker

First extract the image from the docker repository: $ sudo docker pull dockerhelp/docker-oracle-ee-18c
We run the Oracle 18c image and assign a port where it is going to communicate: $ sudo docker run -p 7000:7000 -it dockerhelp/docker-oracle-ee-18c bash
We run the installation file sh: $ sh post_install.sh
We proceed to connect to the database, always inside the container: $ sqlplus
The user who creates us by default is the following: USER: sys as sysdba PASS: oracle
We enter and create a test user SQL> alter session set "_ORACLE_SCRIPT"=true; Session altered. SQL> create user TEST identified by 1234; User created. SQL> grant dba to TEST;

The IP of the container can be found out by exiting the container (without turning it off) with
the key combination ctrl + p and then ctrl + q and running the following commands.

To display all containers that are active. In turn we will display the container id: sudo docker ps
The following command is used to get the ip of the container: sudo docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' [CONTAINER_ID] where "CONTAINER_ID" is the id generated in the previous step.

Third Step: start an existing container in docker

The following commands are run to start the server: sudo docker start aqui_tu_id_del_contenedor sudo docker exec -it aqui_tu_id_del_contenedor bash where "aqui_tu_id_del_contenedor" is the id of the container to start
In the case of oracle 18c, the following commands are executed for sign in: sh post_install.sh sqlplus so we finish the instalation, i hope i helped you :)

DEV Community: Adriana Gómez

Triggers en Oracle (campos autoincrementables)

How to install Oracle 18c and Docker on Ubuntu 20

First Step: installing docker on ubuntu

Second Step: installing oracle 18c on docker

Third Step: start an existing container in docker