How to Set Up Oracle on Linux

What does setting up Oracle on Linux involve?

Installation requires system preparation, software deployment, database creation, listener configuration, and service enablement. Oracle supplies RPM and GUI installers to automate most steps.

What are the prerequisites for Oracle on Linux?

Use a supported distribution (OL 8/9, RHEL 8/9, CentOS 8-stream), 8 GB RAM, 30 GB free disk, swap = RAM, and hostname resolving to a static IP. Disable SELinux or set it to permissive.

Install OS packages in one line

sudo yum install -y oracle-database-preinstall-21c

The preinstall RPM creates oracle groups, users, kernel parameters, ulimits, and required libraries.

How do I install the Oracle software?

RPM-based silent install

# Download from OTN, then
sudo yum localinstall -y oracle-database-ee-21c-1.0-1.x86_64.rpm

RPM places binaries under /opt/oracle/product/21c/dbhome_1 and installs the oracledb service unit.

Configure the database in one command

sudo /etc/init.d/oracledb_ORCLCDB-21c configure

This script sets the CDB name ORCLCDB, listener port 1521, creates a PDB ORCLPDB1, and outputs the generated SYS user password.

How can I connect and verify?

sudo su - oracle
sqlplus sys@ORCLPDB1 as sysdba
SQL> SELECT open_mode FROM v$database;

The query should return READ WRITE, confirming the PDB is open and ready.

How do I create an e-commerce sample schema?

CREATE USER shop IDENTIFIED BY "Sh0pPwd" QUOTA UNLIMITED ON users;
GRANT connect, resource TO shop;

ALTER SESSION SET current_schema = shop;

CREATE TABLE customers (
id NUMBER PRIMARY KEY,
name VARCHAR2(100),
email VARCHAR2(255),
created_at DATE DEFAULT SYSDATE
);

CREATE TABLE products (
id NUMBER PRIMARY KEY,
name VARCHAR2(100),
price NUMBER(10,2),
stock NUMBER
);

CREATE TABLE orders (
id NUMBER PRIMARY KEY,
customer_id NUMBER REFERENCES customers(id),
order_date DATE DEFAULT SYSDATE,
total_amount NUMBER(10,2)
);

CREATE TABLE orderitems (
id NUMBER PRIMARY KEY,
order_id NUMBER REFERENCES orders(id),
product_id NUMBER REFERENCES products(id),
quantity NUMBER
);

These tables mirror a typical online store and help confirm DML functionality after installation.

Best practices after installation

Create a separate ASM or LVM volume for datafiles, enable flashback, schedule RMAN backups, and patch quarterly with opatchauto.

Common mistakes to avoid

Skipping the preinstall RPM causes missing libraries; running the configure script twice corrupts ORACLE_HOME. Always verify logs in /opt/oracle/diag.