Oracle Development: The difference between DBA and SYSDBA

The differences between Oracle DBA and SYSDBA are as follows:

1. A DBA is a role that corresponds to the set of operations permissions on an object in an Oracle instance, and SYSDBA is a conceptual role that is a sign-in authentication identity. Moreover, the DBA is an object in Oracle, and the Role, like user, is a real physical object in Oracle, and SYSDBA refers to a conceptual operand that does not exist in Oracle data.

2, SYSDBA is not a permission, when the user to SYSDBA identity login database, login users will become sys.

SYSDBA Identity login can open, close the database, create SPFile, restore the database, and so on, and these are the DBA role can not be achieved;

SYSDBA is the system permissions (such as login QQ,QQ admin start QQ program), DBA is User object permissions (QQ group owners can manage QQ group such as add people, reduce people, shielding people, etc.);
Before I explain this, I need to talk about the process of creating Oracle Services

• • Create an instance
• • Launch Instances
• • Create a database (System tablespace is required)

Startup process:

• • Instance Launch
• • Loading the database
• • Open Data

SYSDBA, which manages Oracle instances, does not depend on the full start of the entire database,
As soon as the instance is started, he already exists, logs in as SYSDBA, loads the database, opens the database
The DBA role has the basis of existence only if the database is open, or if the entire database is fully started!

Oracle Development: The difference between DBA and SYSDBA