Managing User Privileges and Roles - Oracle DBA

Privileges

A privilege is a permission to execute an action or to access another user’s objects.
The following are a few examples of privileges:

• The right to access the database
• The right to select data from another user’s tables
• The right to execute another user’s stored procedures
• The right to create new users

Types of PRIVILEGES:

• System privileges
• Object privileges.

System privileges enable the user to perform an action on a type of object, where as object privileges give the user permission to perform the action on a specific object.

System privileges:

There are over 100 distinct system privileges. Each system privilege allows a user to perform a particular database operation or class of database operations.

System privileges can be very powerful, and should be granted only when necessary to roles and trusted users of the database.

System privilege table:

System privilege	Operations permitted
Analyze
Analyze any	Audit any schema object in the database.
Audit system	Enable and disable statement and privilege audit options.
Cluster
Create cluster	Create a cluster in own schema.
Create any cluster	Create a cluster in any schema. Behaves similarly to create any table.
Alter any cluster	Alter any cluster in the database.
Drop any cluster	Drop any cluster in the database.
Database
Alter database	Alter the database; add files to the operating system via oracle, regardless of operating system privileges.
Database link
Create database link	Create private database links in own schema.
Index
Create any index	Create an index in any schema on any table.
Alter any index	Alter any index in the database.
Drop any index	Drop any index in the database.
Library
Create library	Create callout libraries in own schema.
Create any library	Create callout libraries in any schema
Drop library	Drop callout libraries in own schema.
Drop any library	Drop callout libraries in any schema.
Privilege
Grant any privilege	Grant any system privilege (not object privileges).
Procedure
Create procedure	Create stored procedures, functions, and packages in own schema.
Create any procedure	Create stored procedures, functions, and packages in any schema. (requires that user also have alter any table, backup any table, drop any table, select any table, insert any table, update any table, delete any table, or grant any table privilege.)
Alter any procedure	Compile any stored procedure, function, or package in any schema.
Drop any procedure	Drop any stored procedure, function, or package in any schema.
Execute any procedure	Execute any procedure or function (stand-alone or packaged), or reference any public package variable in any schema.
Profile
Create profile	Create profiles.
Alter profile	Alter any profile in the database.
Drop profile	Drop any profile in the database.
Alter resourcecost	Set costs for resources used in all user sessions
Public database link
Create public database link	Create public database links.
Drop public database link	Drop public database links.
Public synonym
Create public synonym	Create public synonyms.
Drop public synonym	Drop public synonyms.
Role
Create role	Create roles.
Alter any role	Alter any role in the database.
Drop any role	Drop any role in the database.
Grant any role	Grant any role in the database.
Rollback segment
Create rollback segment	Create rollback segments.
Alter rollback segment	Alter rollback segments.
Drop rollback segment	Drop rollback segments.
Session
Create session	Connect to the database.
Alter session	Issue alter session statements.
Restricted session	Connect when the database has been started using startup restrict. (the osoper and osdba roles contain this privilege.)
Sequence
Create sequence	Create a sequence in own schema.
Create any sequence	Create any sequence in any schema.
Alter any sequence	Alter any sequence in any schema.
Drop any sequence	Drop any sequence in any schema.
Select anysequence	Reference any sequence in any schema
Snapshot
Create snapshot	Create snapshots in own schema. (user must also have the create table privilege.)
Create snapshot	Create snapshots in any schema. (user must also have the create any table privilege.)
Alter snapshot	Alter any snapshot in any schema.
Drop any snapshot	Drop any snapshot in any schema.
Synonym
Create synonym	Create a synonym in own schema.
Create synonym	Create any synonym in any schema.
Drop any synonym	Drop any synonym in any schema.
System
Alter system	Issue alter system statements.
Table
Create table	Create tables in own schema. Also allows grantee to create indexes (including those for integrity constraints) on table in own schema. (the grantee must have a quota for the tablespace or the unlimited tablespace privilege.)
Create any table	Create tables in any schema. (if grantee has create any table privilege and creates a table in another user’s schema, the owner must have space quota on that tablespace. The table owner need not have the create [any] table privilege.)
Alter any table	Alter any table in any schema and compile any view in any schema.
Backup any table	Perform an incremental export using the export utility of tables in any schema.
Drop any table	Drop or truncate any table in any schema.
Lock any table	Lock any table or view in any schema.
Comment any table	Comment on any table, view, or column in schema.
Select any table	Query any table, view, or snapshot in any schema.
Insert any table	Insert rows into any table or view in any schema.
Update any table	Update rows in any table or view in any schema.
Delete any table	Delete rows from any table or view in any schema.
Tablespace
Create tablespace	Create tablespaces; add files to the operating system via oracle, regardless of the user’s operating system privileges.
Alter tablespace	Alter tablespaces; add files to the operating system via oracle, regardless of the user’s operating system privileges.
Manage tablespace	Take any tablespace offline, bring any tablespace online, and begin and end backups of any tablespace
Drop tablespace	Drop tablespaces
Unlimited tablespace	Use an unlimited amount of any tablespace. This privilege overrides any specific quotas assigned. If revoked, the grantee’s schema objects remain but further tablespace allocation is denied unless allowed by specific tablespace quotas. This system privilege can be granted only to users and not to roles. In general, specific tablespace quotas are assigned instead of granting this system privilege.
Transaction
Force transaction	Force the commit or rollback of own in-doubt distributed transaction in the local database.
Force any transaction	Force the commit or rollback of any in-doubt distributed transaction in the local database.
Trigger
Create trigger	Create a trigger in own schema.
Create any trigger	Create any trigger in any schema associated with any table in any schema.
Alter any trigger	Enable, disable, or compile any trigger in any schema
Drop any trigger	Drop any trigger in any schema.
User
Create any user	Create users; assign quotas on any tablespace, set default and temporary tablespaces, and assign a profile as part of a create user statement.
Become any user	Become another user. (required by any user performing a full database import.)
Alter user	Alter other users: change any user’s password or authentication method, assign tablespace quotas, set default and temporary tablespaces, assign profiles and default roles, in an alter user statement. (not required to alter own password.)
Drop user	Drop another user.
View
Create view	Create a view in own schema.
Create any view	Create a view in any schema. To create a view in another user’s schema, you must have create any view privileges, and the owner must have the required privileges on the objects referenced in the view.
Drop any view	Drop any view in any schema.

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Accessing objects in the sys schema:

Users with explicit object privileges or those who connect with administrative privileges (sysdba) can access objects in the sys schema. Another means of allowing access to objects in the sys schema is by granting users any of the following roles:

• Select_catalog_role

This role can be granted to users to allow select privileges on data dictionary views.

• Execute_catalog_role

                         This role can be granted to users to allow execute privileges for packages and procedures in the data dictionary.

• Delete_catalog_role

                          This role can be granted to users to allow them to delete records from the system audit table (aud$).

Additionally, the following system privilege can be granted to users who require access to tables created in the sys schema:

• Select any dictionary

This system privilege allows query access to any object in the sys schema, including tables created in that schema. It must be granted individually to each user requiring the privilege. It is not included in grant all privileges, but it can be granted through a role.

$ Accessing frequently used dictionay objects:

Users with explicit object privileges and the sysdba can access dictionary objects. If, however, you need access to dictionary objects and do not have explicit object privileges, you can be granted the following roles:

• Select_catalog_role

                             Enables users to select all exported catalog views and tables granted to this role. Grant this role to users who must access all exported views and tables in the data dictionary.

• Execute_catalog_role

                                  Provides execute privilege on exported packages in the dictionary.

• Delete_catalog_role

                                  Enables users to delete records from the aud$ table.

These roles enable database administrators to access certain objects in the dictionary while maintaining dictionary security.

Object privileges:

Each type of object has different privileges associated with it.

Object privilege	Sql statements permitted
Alter	Alter object (table or sequence)
Delete	Delete from object (table or view)
Execute	Execute object (procedure or function).references to public package variables
Index	Create index on object (tables only)
Insert	Insert into object (table or view)
References	Create or alter table statement defining a foreign key integrity constraint on object (tables only)
Select	Select…from object (table, view, or snapshot). Sql statements using a sequence
Update	Update object (table or view)

 

Object privilege shortcut:

The all and all privileges shortcuts grant or revoke all available object privileges for a object. This shortcut is not a privilege, rather, it is a way of granting or revoking all object privileges with one word in grant and revoke statements. Note that if all object privileges are granted using the all shortcut, individual privileges can still be revoked.

Likewise, all individually granted privileges can be revoked using the all shortcut. However, if you revoke all, and revoking causes integrity constraints to be deleted (because they depend on a references privilege that you are revoking), you must include the cascade constraints option in the revoke statement.