Connecting to the Database with SQL*Plus
Submit the SQL*Plus CONNECT Statement
You submit the SQL*Plus CONNECT statement to initially connect to the Oracle instance or at any time to reconnect as a different user. The syntax of the CONNECT statement is as follows:
CONN[ECT] [logon] [AS {SYSOPER | SYSDBA}]
The syntax of logon is as follows:
{username | /}[@connect_identifier] [edition={edition_name | DATABASE_DEFAULT}]
When you provide username, SQL*Plus prompts for a password. The password is not echoed as you type it.
The following table describes the syntax components of the CONNECT statement.
| Syntax Component | Description |
|---|---|
| / | Calls for external authentication of the connection request. A database password is not used in this type of authentication. The most common form of external authentication is operating system authentication, where the database user is authenticated by having logged in to the host operating system with a certain host user account. External authentication can also be performed with an Oracle wallet or by a network service. See Oracle Database Security Guide for more information. See also "Using Operating System Authentication". |
| AS {SYSOPER | SYSDBA} | Indicates that the database user is connecting with either the SYSOPER or SYSDBA system privilege. Only certain predefined administrative users or users who have been added to the password file may connect with these privileges. See "Administrative Privileges" for more information. |
| username | A valid database user name. The database authenticates the connection request by matching username against the data dictionary and prompting for a user password. |
| connect_identifier (1) |
An Oracle Net connect
identifier, for a remote connection. The exact syntax depends on the
Oracle Net configuration. If omitted, SQL*Plus attempts connection to a
local instance.
A common connect identifier is a net service name. This is an alias for an Oracle Net connect descriptor (network address and database service name). The alias is typically resolved in the tnsnames.ora file on the local computer, but can be resolved in other ways. See Oracle Database Net Services Administrator's Guide for more information on connect identifiers. |
| connect_identifier (2) |
As an alternative, a connect identifier can use easy connect syntax. Easy connect provides out-of-the-box TCP/IP connectivity for
remote databases without having to configure Oracle Net Services on the
client (local) computer.
Easy connect syntax for the connect identifier is as follows (the enclosing double-quotes must be included): "host[:port][/service_name][:server][/instance_name]" where:
See Oracle Database Net Services Administrator's Guide for more information on easy connect. |
| edition={edition_name | DATABASE_DEFAULT} |
Specifies the edition in which the new database session starts. If you specify an edition, it must exist and you must have the USE privilege on it. If this clause is not specified, the database default edition is used for the session.
See Oracle Database Advanced Application Developer's Guide for information on editions and edition-based redefinition. |
This simple example connects to a local database as user SYSTEM. SQL*Plus prompts for the SYSTEM user password.
connect system
This example connects to a local database as user SYS with the SYSDBA privilege. SQL*Plus prompts for the SYS user password.
connect sys as sysdba
When connecting as user SYS, you must connect AS SYSDBA.
This example connects locally with the SYSDBA privilege with operating system authentication.
connect / as sysdba
Example 1-6
This example uses easy connect syntax to connect as user salesadmin to a remote database running on the host dbhost.example.com. The Oracle Net listener (the listener) is listening on the default port (1521). The database service is sales.example.com. SQL*Plus prompts for the salesadmin user password.
connect salesadmin@"dbhost.example.com/sales.example.com"
This example is identical to , except that the service handler type is indicated.
connect salesadmin@"dbhost.example.com/sales.example.com:dedicated"
Example 1-8
This example is identical to , except that the listener is listening on the nondefault port number 1522.
connect salesadmin@"dbhost.example.com:1522/sales.example.com"
This example is identical to , except that the host IP address is substituted for the host name.
connect salesadmin@"192.0.2.5/sales.example.com"
This example connects using an IPv6 address. Note the enclosing square brackets.
connect salesadmin@"[2001:0DB8:0:0::200C:417A]/sales.example.com"
This example specifies the instance to which to connect and omits the database service name. A default database service must have been specified, otherwise an error is generated. Note that when you specify the instance only, you cannot specify the service handler type.
connect salesadmin@"dbhost.example.com//orcl"
This example connects remotely as user salesadmin to the database service designated by the net service name sales1. SQL*Plus prompts for the salesadmin user password.
connect salesadmin@sales1
This example connects remotely with external authentication to the database service designated by the net service name sales1.
connect /@sales1
This example connects remotely with the SYSDBA privilege and with external authentication to the database service designated by the net service name sales1.
connect /@sales1 as sysdba
This example connects remotely as user salesadmin to the database service designated by the net service name sales1. The database session starts in the rev21 edition. SQL*Plus prompts for the salesadmin user password.
connect salesadmin@sales1 edition=rev21
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