Introduction to Oracle SQL*Plus

SQL*Plus is Oracle Database’s command-line client for connecting, running SQL and PL/SQL, and performing basic administration tasks. For scripting-heavy workflows, many teams also use SQLcl (a modern CLI with command history and scripting niceties). Browser-based iSQL*Plus is discontinued.

Prerequisites

• Oracle Database or the Oracle Client installed.
• A database user with credentials (from your DBA or during install).
• A connection identifier (Easy Connect, TNS alias, or net service name).
• The target database is up and reachable over the network.

Common Tasks

1. Start SQL*Plus and connect to a database.
2. Check help for SQL*Plus commands (environment, formatting, spooling).
3. Describe tables and views.
4. Run queries and review results.
5. Write output to a file (spool).
6. Optional (DBA only): start up or shut down a database when connected as SYSDBA.

Quick Examples

Connect

sqlplus username@//host:port/service_name
-- or on the same host:
-- sqlplus / as sysdba

Describe a table and query data

DESCRIBE hr.employees;

SELECT first_name, last_name, department_id
FROM   hr.employees
WHERE  ROWNUM <= 5;

Write output to a file (spool)

SPOOL /tmp/report.txt
SELECT COUNT(*) AS rows_in_emp FROM hr.employees;
SPOOL OFF

Related: Monitoring with Enterprise Manager Cloud Control

SQL*Plus is ideal for ad-hoc SQL and scripting. For fleet monitoring, alerting, and job automation, use Enterprise Manager Cloud Control.