Installing Oracle & SQL Developer

Before you can run a single query, you need a working Oracle environment. This lesson walks you through installing Oracle Database Express Edition (XE) — the free edition used throughout this course — and Oracle SQL Developer, the free graphical tool used to write and run SQL. By the end of this lesson you will have a fully functional local Oracle database and a connected client tool ready for every practical exercise in the course.

What You Are Installing and Why

Two separate pieces of software are needed to work with Oracle on your machine.

Oracle Database XE is the database server. It runs as a background service on your computer and manages all data storage, query execution, and transaction processing. It is the engine. You do not interact with it directly — you connect to it through a client tool.

Oracle SQL Developer is the client tool. It is a free graphical application provided by Oracle that lets you write SQL, run queries, view table data, manage schema objects, and see query results — all through a visual interface. It connects to the Oracle XE server running on your machine.

Think of it this way: Oracle XE is the kitchen, SQL Developer is how you place your order. Both need to be installed and connected before you can do any work.

• Oracle XE and SQL Developer are both free — no licence or payment is required for either
• SQL Developer requires Java to run — Oracle bundles a compatible JDK version with SQL Developer so you do not need to install Java separately
• Both tools are free and available for Windows, macOS, and Linux — download links are in the Summary section below

Installing Oracle Database XE

Follow these steps in order. The steps apply to Windows, which is the most common environment for learners. Notes for macOS and Linux are included where the process differs.

1. Download Oracle XE — click the link below to go to the Oracle XE downloads page and select Oracle Database 21c Express Edition (or the latest available XE version). Choose the installer for your operating system.
   
   Download Oracle Database XE
2. Run the installer — on Windows, right-click the downloaded .exe file and select Run as Administrator. Accept the licence agreement and follow the prompts. On Linux, use the RPM or Debian package appropriate for your distribution.
3. Set the passwords — during installation you will be asked to set a password for the system database accounts: SYS, SYSTEM, and PDBADMIN. Use a password you will remember — you need it to connect. Write it down securely.
4. Note the connection details — the installer will show you the connection information when it completes. The default hostname is localhost, the default port is 1521, and the service name for XE is XE (or XEPDB1 for the pluggable database, which is what most queries in this course use).
5. Verify the installation — on Windows, open Command Prompt and type sqlplus / as sysdba. If Oracle is installed correctly, you will see the SQL*Plus prompt. Type SELECT 1 FROM DUAL; and press Enter. If it returns 1, Oracle is running.

• On Windows, Oracle XE installs as a Windows service called OracleServiceXE — it starts automatically when your computer boots. You can stop and start it from Windows Services if needed.
• On macOS, Oracle does not provide a native installer — the recommended approach is to run Oracle XE inside a Docker container using the official Oracle Docker image.
  
  Oracle Container Registry
• If the installer fails or the service does not start, the most common cause is insufficient RAM — Oracle XE requires at least 2 GB of available memory to start

Installing Oracle SQL Developer

SQL Developer is separate from the database and must be installed independently. It is a Java application packaged as a simple download — there is no traditional installer wizard.

1. Download SQL Developer — click the link below and download the version labelled "with JDK included" — this bundles the required Java runtime so you do not need a separate Java installation.
   
   Download Oracle SQL Developer
2. Extract the archive — SQL Developer comes as a ZIP file. Extract it to a folder on your computer such as C:\SQLDeveloper on Windows or /Applications/SQLDeveloper on macOS. There is no installer — extracting the ZIP is the complete installation.
3. Launch SQL Developer — on Windows, open the extracted folder and double-click sqldeveloper.exe. On macOS, double-click the sqldeveloper.app file. On first launch, SQL Developer may ask whether to import settings from a previous version — select No if this is a fresh install.
4. Create a new connection — in SQL Developer, click the green plus icon in the Connections panel on the left, or go to File → New → Database Connection. Fill in the connection details as follows.
5. Test and connect — click the Test button. If the Status at the bottom shows "Success", click Connect. You are now connected to your local Oracle XE database.

Connection Details for Oracle XE

When creating your connection in SQL Developer, use the following values:

• Use XEPDB1 as the service name rather than XE — XEPDB1 is the pluggable database (PDB) where you create your own schemas and tables; XE is the container database (CDB) used for administration
• Select Service Name in the Connection Type dropdown, not SID — SID is the older connection method and may not work correctly with modern Oracle XE versions
• If you prefer not to install anything locally, Oracle Live SQL is a free browser-based Oracle SQL environment that requires only a free Oracle account — all SQL in this course works there without any local installation.
  
  Open Oracle Live SQL

A Quick Tour of SQL Developer

Once connected, SQL Developer has four areas you will use constantly.

• Connections panel (left) — shows all your saved database connections and lets you expand them to browse tables, views, sequences, and other schema objects
• SQL Worksheet (centre) — the main area where you type and run SQL. Press F5 to run a script (all statements), or Ctrl + Enter to run the single statement the cursor is on
• Query Result panel (bottom) — displays the rows returned by a SELECT statement in a grid format
• Script Output panel (bottom) — shows the text output when running scripts with DBMS_OUTPUT or DDL statements

Two keyboard shortcuts save you the most time early on:

• Ctrl + Enter — run the current SQL statement
• F5 — run the entire worksheet as a script

Summary

Practice Questions

Quiz

Next up — Oracle Database Architecture — Understand how Oracle organises its memory, processes, and storage internally so that everything you do as a developer or DBA makes sense from the ground up.