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Oracle的表空间quota详解

Oracle的表空间quota详解
 
当你创建用户的时候, 如下:
 
SQL> CREATE USER user01
IDENTIFIED BY oracle
DEFAULT TABLESPACE tbs1
TEMPORARY TABLESPACE temp
PROFILE default
SQL> GRANT create session, create table TO user01;
While executing the command to create a table, the user gets the following error message and the CREATE
TABLE.. command fails.
ERROR at line 1:
ORA-01950: no privileges on tablespace
 
解释: default tablespace 是定义了用户在不写明表空间时,使用的表空间,而因表空间管理的要求,oracle必须要能管理他(用户)的可用大小,就有了quota子句.
 
  GRANT create session, create table TO user01 是指user01拥有了建表的权限 ,oracle 也知道了他也有了默认的表空间,但默认的表空间没有给他分配空间,所以出错。你可以在建用户时加上quota 200M on tbs1 (给他200M 空间) 或直接 alter user user01 unlimited on tbs1 (让他随意使用tbs1表空间)。所以在建用户的过程中,需要让默认的表空间给该用户分配空间(也可以分配无限使用),当此用户用到表空间的配额后,再也不能使用空间,除非再次申请。
 
表空间quota概述
 
Oracle 官网对quota的定义如下: A limit on a resource, such as a limit on the amount of database storage used by a database user. A database administrator can set tablespace quotas for each Oracle Database username
 
quota的日常管理
 
常见问题
 
ORA-01536: space quota exceeded for table space 'CYYD'
 
ORA-01950: no privileges on tablespace 
解决办法: 
alter user USERNAME quota 100M on TABLESPACENAME; 
alter user USERNAME quota unlimited on TABLESPACENAME;
grant unlimited tablespace to USERNAME;
 
注:quota是为了限制用户对表空间的使用,比如你限制用户Guotu在tablespace CYYD中的quota为10m,当用户Guotu在tablespace CYYD中的数据量达到10m后,无论你的tablespace CYYD中有多少空间,Guotu都无法再使用tablespace CYYD了。
 
所以你需要: 
alter user aGuotu quota 1000M on CYYD;
alter user Guotu quota unlimited on CYYD;
grant unlimited tablespace to Guotu
 
dba_ts_quotas
 
与quota相关的数据字典视图为dba_ts_quotas,以下是相关的信息
Assigning a Tablespace Quota for the User
You can assign each user a tablespace quota for any tablespace (except a temporary tablespace). Assigning a quota accomplishes the following:
Users with privileges to create certain types of objects can create those objects in the specified tablespace.
Oracle Database limits the amount of space that can be allocated for storage of a user's objects within the specified tablespace to the amount of the quota.
By default, a user has no quota on any tablespace in the database. If the user has the privilege to create a schema object, then you must assign a quota to allow the user to create objects. At a minimum, assign users a quota for the default tablespace, and additional quotas for other tablespaces in which they can create objects.
 
可以使用下列语句来创建用户
CREATE USER jward
IDENTIFIED BY password
DEFAULT TABLESPACE data_ts
QUOTA 100M ON test_ts
QUOTA 500K ON data_ts
TEMPORARY TABLESPACE temp_ts
PROFILE clerk;
 
配额的指定可以禁止用户的对象使用过多的表空间
 
You can assign a user either individual quotas for a specific amount of disk space in each tablespace or an unlimited amount of disk space in all tablespaces. Specific quotas prevent a user's objects from using too much space in the database.
You can assign quotas to a user tablespace when you create the user, or add or change quotas later. (You can find existing user quotas by querying the USER_TS_QUOTAS view.) 。
If a new quota is less than the old one, then the following conditions remain true:
(1)If a user has already exceeded a new tablespace quota, then the objects of a user in the tablespace cannot be allocated more space until the combined space of these objects is less than the new quota.
(2)If a user has not exceeded a new tablespace quota, or if the space used by the objects of the user in the tablespace falls under a new tablespace quota, then the user's objects can be allocated space up to the new quota.
Restricting the Quota Limits for User Objects in a Tablespace 
You can restrict the quota limits for user objects in a tablespace by using the ALTER USER SQL statement to change the current quota of the user to zero.
After a quota of zero is assigned, the objects of the user in the tablespace remain, and the user can still create new objects, but the existing objects will not be allocated any new space.
For example, you could not insert data into one of this user's exiting tables. The operation will fail with an ORA-1536 space quota exceeded for tables error.
Granting Users the UNLIMITED TABLESPACE System Privilege
To permit a user to use an unlimited amount of any tablespace in the database, grant the user the UNLIMITED TABLESPACE system privilege. This overrides all explicit tablespace quotas for the user. If you later revoke the privilege, then you must explicitly grant quotas to individual tablespaces. You can grant this privilege only to users, not to roles.
Before granting the UNLIMITED TABLESPACE system privilege, you must consider the consequences of doing so.
Advantage:
You can grant a user unlimited access to all tablespaces of a database with one statement.
Disadvantages:
(1)The privilege overrides all explicit tablespace quotas for the user.
(2)You cannot selectively revoke tablespace access from a user with the UNLIMITED TABLESPACE privilege. You can grant selective or restricted access only after revoking the privilege.
Listing All Tablespace Quotas
Use the DBA_TS_QUOTAS view to list all tablespace quotas specifically assigned to each user. For example: 
SELECT * FROM DBA_TS_QUOTAS;
TABLESPACE USERNAME BYTES MAX_BYTES BLOCKS MAX_BLOCKS
---------- --------- -------- ---------- ------- ----------
USERS JFEE 0 512000 0 250
USERS DCRANNEY 0 -1 0 -1 
When specific quotas are assigned, the exact number is indicated in the MAX_BYTES column . This number is always a multiple of the database block size, so if you specify a tablespace quota that is not a multiple of the database block size, then it is rounded up accordingly. Unlimited quotas are indicated by -1.
 
 
 
注意当对用户赋予resource角色时将同时赋予unlimited tablespace的系统权限。详情见下文
 
 
 
创建用户 
 
SQL> create user test_privs identified by test_privs default tablespace users;
User created.
 
SQL> select * from dba_sys_privs where GRANTEE='TEST_PRIVS';
no rows selected 
赋予resource角色
SQL> grant resource to TEST_PRIVS;
Grant succeeded. 
 
查询resource角色所具有的系统权限
 
SQL> select * from dba_sys_privs where GRANTEE='RESOURCE';
 
GRANTEE PRIVILEGE ADM
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