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Introducing SQL*Plus

This chapter provides introductory information to help you get started with SQL*Plus.

Specific topics discussed are:

• Overview

• Basic Concepts

• Obtaining Online Help

Overview

You can use the SQL*Plus tool with SQL (Structured Query Language) and its procedural language extension, PL/SQL. These database languages allow you to store and retrieve data in Oracle databases. PL/SQL allows you to link several SQL commands through procedural logic.

SQL*Plus enables you to manipulate SQL commands and PL/SQL blocks, and to perform many additional tasks. With SQL*Plus, you can:

• Enter, edit, store, retrieve, and run SQL commands and PL/SQL blocks.

• Format, perform calculations on, store, and print query results in the form of reports.

• List column definitions for any table.

• Access and copy data between databases.

• Send messages to and accept responses from an end user.

• Perform database administration.

SQL*Plus provides both a command line interface and a graphical user interface (GUI). See Chapter 3, "Using SQL*Plus" for more information.

Basic Concepts

The following definitions explain concepts central to SQL*Plus:

Concept	Definition
command	An instruction you give to an operating system, or software such as SQL*Plus or Oracle, to perform a particular task.
SQL command	A command to execute SQL statements.
SQL*Plus command	A command to execute SQL*Plus statements.
block	In PL/SQL, a group of SQL and PL/SQL commands related to each other through procedural logic.
table	The basic unit of storage in Oracle.
query	A read only SQL SELECT command that retrieves information from one or more tables.
query results	The data retrieved by a query.
report	Query results formatted by you through SQL*Plus commands.
SQL buffer	A buffer which stores the last SQL command or PL/SQL block that you entered in SQL*Plus.
screen buffer	A buffer to store the data in the SQL*Plus application window.

For definitions of other concepts that are relevant to SQL*Plus, see the glossary in the SQL*Plus User's Guide and Reference.

Obtaining Online Help

Online help for SQL*Plus is available from the SQL*Plus command line during a session. The SQL*Plus help tables must be created and populated by the database administrator. See "Installing SQL*Plus Online Help" in Chapter 2 for information about installing SQL*Plus online help.