Differences between SYS and system users in Oracle

1. The start of the database needs to be logged in as Sysdba/sysoper.

2. If you use IPC to connect to a database on the same host using the operating system authorization, any user who logs on can have as SYSDBA and as Sysoper.

The difference between 3.sys and system users

SYS user has DBA authority and has the SYS mode. The database can only be logged on through SYSDBA and is the highest-privileged account in the Oracle database. SYS user has "SYSDBA" and "sysoper" permission, login em can only use these two identities, can not use normal. The system can only log in with normal mode when logging on to EM. SYS has a data dictionary (dictionary), or dictionary belongs to the SYS schema.

The system user has DBA authority, but does not have SYSDBA permissions. Usually use this account to manage the database. Log in to EM only with normal login.

4.SYSDBA Permissions and Sysoper permission differences

"Sysoper" permissions, that is, database operator permissions, Sysoper is mainly used to start, close the database, Sysoper login after the user is public. Permissions include: Open Database (STARTUP, ALTER database Open/mount/open), server (CREATE spfile,etc)

Shutting down the database server
Backing Up the database
Recovering a database recovery
Log Archive Archivelog
Session Limit restricted sessions

"SYSDBA" permissions, that is, database administrator permissions, the highest system permissions. Any user with SYSDBA login is "SYS". Permissions include: Administrative functions, creation of databases (create DATABASE), and all permissions for "Sysoper"

The other user needs the manual grant permission, which is the name of the user.

Sql>conn/as SYSDBA
is connected.
Sql>grant sysoper to test;
Authorization is successful.
Sql>grant sysdba to test;
Authorization is successful.
Sql>conn Test/test as Sysoper;
is connected.
Sql>show User
USER is "public"
Sql>conn Test/test as SYSDBA;
is connected.
Sql>show user;
USER is "SYS"
Sql>conn test/test;
is connected.
Sql>show User
USER is "test"

The difference between 5.DBA and SYSDBA:

SYSDBA, is the management Oracle instance, its existence does not depend on the entire database to start completely, as long as the instance launches, he already exists, in order to sysdba the identity to log in, mounts the database, opens the database.

The DBA role has the basis for existence only after the database is fully booted.

Differences between SYS and system users in Oracle