About SQL and SQL-Based Management Tools

About SQL*Plus

SQL*Plus is a command-line program that you use to submit SQL and PL/SQL statements to an Oracle database. You can submit statements interactively or as SQL*Plus scripts. SQL*Plus is installed with the database and is located in your Oracle_home/bin directory.

You can start SQL*Plus from the command line, or on Microsoft Windows, from the Start menu.

When SQL*Plus loads, it issues the SQL prompt, which looks like this:

SQL>

At the SQL prompt, you can enter statements that perform administrative tasks such as shutting down the database or creating a new user, or you can query, insert, update, and delete data.

You can enter a single SQL statement on multiple lines. You must end each statement with a semicolon (;). For most statements, you can rerun a statement by entering a forward slash (/) on a line by itself.

Starting SQL*Plus and Connecting to the Database

The section describes how to start SQL*Plus and connect to the database from both the command line and the Windows start menu.

To start SQL*Plus and connect to the database from the command line:

1. Open a command window.

2. (Linux and UNIX systems only) Set the required environment variables (ORACLE_HOME and ORACLE_SID) by running the script oraenv (for the Bourne, Korn, or Bash shell) or coraenv (for the C shell).

   These scripts are typically located in the /usr/local/bin directory. They may prompt you for the desired value of the ORACLE_SID environment variable. If so, supply the system ID (SID) that you chose when you installed Oracle Database. The default SID that the installer typically suggests is orcl.

3. (Linux and UNIX systems only) Either ensure that the Oracle_home/bin directory is in your PATH environment variable, or change to the Oracle_home/bin directory.

4. Enter the following command:

   sqlplus {username | /} [as sysdba]
   Enter password: password
   

   SQL*Plus connects you to the default database instance (Microsoft Windows) or the database instance specified by the environment variables (Linux and UNIX).

   For username, you can use the SYS or SYSTEM administrative users. At the prompt, enter the password that you set up during installation. If you use the SYS user, you must include as sysdba after the username.

   When you enter SYS or a slash (/) as the user name and provide the as sysdba clause, you are authenticating using operating system authentication. Operating system authentication uses your Windows, UNIX, or Linux host user account to authenticate you to Oracle Database. You must have logged in to the host computer with a user account that is a member of a special host user group. On UNIX and Linux, this user group is typically dba. This type of authentication enables you to connect to an Oracle database that is not yet started, so that you can start it up. See Oracle Database Administrator's Guide for more information.

To start SQL*Plus and connect to the database from the Windows Start menu:

1. Click Start, select Programs (or All Programs), then Oracle - HOME_NAME, then Application Development, and then SQL*Plus.

2. When prompted, enter the user name and password for the account that you want to use to connect to the database.

   For the user name, you can use the SYS or SYSTEM administrative accounts, and you can use the password that you set up during installation.

   If you use SYS or / as the user name, follow them with a space and then the clause as sysdba, as shown in the following examples:

   Enter user-name: sys as sysdba
   Enter password: password
   
   or
   
   Enter user-name: / as sysdba
   

   When you enter SYS or a slash (/) as the user name and provide the as sysdba clause, you are authenticating using operating system authentication. Operating system authentication uses your Windows, UNIX, or Linux host user account to authenticate you to Oracle Database. You must have logged in to the host computer with a user account that is a member of a special host user group. On UNIX and Linux, this user group is typically dba for the sysdba privilege. This type of authentication enables you to connect to an Oracle database that is not yet started, so that you can start it up. See Oracle Database Administrator's Guide for more information.

About SQL Developer

SQL Developer provides another graphical user interface for accessing your Oracle database. SQL Developer supports development in both the SQL and PL/SQL languages. It is available in the default installation of Oracle Database.

With SQL Developer, you can browse database objects, run SQL statements and SQL scripts, and edit and debug PL/SQL statements. You can also run any number of provided reports, as well as create and save your own.