Oracle Road (1)-user management;

1 Oracle user

Oracle Installation will automatically generate sys and system users:

(1) A sys user is a super user with the highest permissions, sysdba role, and createdatabase permissions. The default password for this user is change_on_install.

(2) The system user is a management operator with a high level of permissions. Has the sysoper role and does not have the create database permission. The default password is Manager.

(3) generally, you can use the System user to log on to the database for database maintenance.

That is to say, the biggest difference between sys and system is whether they have the create database permission.

2. Create a user

create user empidentified by a123456;

Of course, you can specify the default and temporary tablespaces.

create uses empidentified by a123456default tablespace userstemporary tablespace temp;

(It seems that the newly created user in the user tablespace space has the DBA permission. At least on my local machine .)

If the tablespace is not specified, authorization is required to connect to the database.

Grant connect to EMP; grant create table to EMP; // create table permission grant select on student to EMP; // query table permission grant update on student to EMP; // update table permissions grant all on EMP to EMP; // grant edit/delete/query Permissions

Revoke permissions:

revoke select on student from emp;

If you want to grant permissions:

For object permissions:

grant select on student to emp with grant option

For system permissions:

grant select on student to emp with admin option