Overview of SQL*Plus

You can use the SQL*Plus program in conjunction with the SQL database language and its procedural language extension, PL/SQL. The SQL database language allows you to store and retrieve data in Oracle. PL/SQL allows you to link several SQL commands through procedural logic.

SQL*Plus enables you to execute SQL commands and PL/SQL blocks, and to perform many additional tasks as well. Through SQL*Plus, you can

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

• format, perform calculations on, store, print and create web output of query results

• list column definitions for any table

• access and copy data between SQL databases

• send messages to and accept responses from an end user

• perform database administration

Basic Concepts

The following definitions explain concepts central to SQL*Plus:

command	An instruction you give SQL*Plus or Oracle.
block	A group of PL/SQL commands related to one another through procedural logic.
table	The basic unit of storage in Oracle.
query	A 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.

Who Can Use SQL*Plus

The SQL*Plus, SQL, and PL/SQL command languages are powerful enough to serve the needs of users with some database experience, yet straightforward enough for new users who are just learning to work with Oracle.

The design of the SQL*Plus command language makes it easy to use. For example, to give a column labelled LAST_NAME in the database the clearer heading "Last Name", you might enter the following command:

COLUMN LAST_NAME HEADING 'Last Name'

Similarly, to list the column definitions for a table called EMPLOYEES, you might enter this command:

DESCRIBE EMPLOYEES