如何删除Oracle LOB
以下查询可用于列出用户的数据库对象:如何删除Oracle LOB,oracle,lob,Oracle,Lob,以下查询可用于列出用户的数据库对象: select object_name, object_type from user_objects; 有两个条目的对象类型为LOB 如何在Oracle中删除这些LOB对象?如果删除包含关联LOB列的表或从该表中删除LOB列,则LOB对象将被删除。根据您的权限,您可以通过查询DBA\u LOB、ALL\u LOB或USER\u LOB来查看特定LOB对象支持的列 比如说 SELECT l.table_name, l.column_name,
select object_name, object_type from user_objects;
有两个条目的对象类型为LOB
如何在Oracle中删除这些LOB对象?如果删除包含关联LOB列的表或从该表中删除LOB列,则LOB对象将被删除。根据您的权限,您可以通过查询
DBA\u LOB
、ALL\u LOB
或USER\u LOB
来查看特定LOB对象支持的列
比如说
SELECT l.table_name,
l.column_name,
l.segment_name lob_name
FROM user_lobs l
JOIN user_objects o
ON( o.object_name = l.segment_name )
将向您显示模式中每个
LOB
对象支持的表和列。在一种场景中,您可以在user\u objects
中看到LOB,但是与user\u LOB
的连接没有找到任何内容,即如果表已被删除,但是
正如所料,Justin的查询向您显示以下列:
select l.table_name,
l.column_name,
l.segment_name lob_name
from user_lobs l
join user_objects o
on( o.object_name = l.segment_name );
TABLE_NAME COLUMN_NAME LOB_NAME
----------- ----------- ------------------------------
T42 MY_CLOB SYS_LOB0000133310C00001$$
drop table t42;
table T42 dropped.
现在Justin的查询没有找到任何内容:
select l.table_name,
l.column_name,
l.segment_name lob_name
from user_lobs l
join user_objects o
on( o.object_name = l.segment_name );
no rows selected
但它仍然在用户对象中
:
select object_name, object_type, status from user_objects
where object_type like 'LOB%';
OBJECT_NAME OBJECT_TYPE STATUS
------------------------------ ------------------- -------
SYS_LOB0000133328C00001$$ LOB VALID
您可以在回收站中看到它:
select * from user_recyclebin;
OBJECT_NAME ORIGINAL_NAME OPERATION TYPE TS_NAME CREATETIME DROPTIME DROPSCN PARTITION_NAME CAN_UNDROP CAN_PURGE RELATED BASE_OBJECT PURGE_OBJECT SPACE
------------------------------ -------------------------------- --------- ------------------------- ------------------------------ ------------------- ------------------- ---------- -------------------------------- ---------- --------- ---------- ----------- ------------ ----------
SYS_IL0000133310C00001$$ SYS_IL0000133310C00001$$ DROP LOB INDEX USERS 2013-08-22:08:33:21 2013-08-22:08:33:21 1.0E+13 NO NO 133310 133310 133310 0
SYS_LOB0000133310C00001$$ SYS_LOB0000133310C00001$$ DROP LOB USERS 2013-08-22:08:33:21 2013-08-22:08:33:21 1.0E+13 NO NO 133310 133310 133310 0
BIN$5IUNXtWkUXLgQwEAAH9TlQ==$0 T42 DROP TABLE USERS 2013-08-22:08:33:21 2013-08-22:08:33:21 1.0E+13 YES YES 133310 133310 133310 0
LOB仍然存在于磁盘上,并且正在使用存储,我想这正是您所关心的。因此,为了回答您的问题,要真正删除LOB并释放其存储,您需要清除整个表:
purge table t42;
table purged.
select object_name, object_type, status from user_objects
where object_type like 'LOB%';
no rows selected
有趣的是,如果将LOB段命名为:
create table t42 (my_clob clob)
lob (my_clob) store as my_clob_segment;
重复上述步骤,在下拉
之后,条目已从用户对象
中删除
drop table t42;
table T42 dropped.
select object_name, object_type, status from user_objects
where object_type like 'LOB%';
no rows selected
select * from user_recyclebin;
OBJECT_NAME ORIGINAL_NAME OPERATION TYPE TS_NAME CREATETIME DROPTIME DROPSCN PARTITION_NAME CAN_UNDROP CAN_PURGE RELATED BASE_OBJECT PURGE_OBJECT SPACE
------------------------------ -------------------------------- --------- ------------------------- ------------------------------ ------------------- ------------------- ---------- -------------------------------- ---------- --------- ---------- ----------- ------------ ----------
BIN$5IUNXtWnUXLgQwEAAH9TlQ==$0 MY_CLOB_SEGMENT DROP LOB USERS 2013-08-22:08:36:41 2013-08-22:08:36:41 1.0E+13 NO NO 133316 133316 133316 0
BIN$5IUNXtWoUXLgQwEAAH9TlQ==$0 T42 DROP TABLE USERS 2013-08-22:08:36:41 2013-08-22:08:36:41 1.0E+13 YES YES 133316 133316 133316 0
SYS_IL0000133316C00001$$ SYS_IL0000133316C00001$$ DROP LOB INDEX USERS 2013-08-22:08:36:41 2013-08-22:08:36:41 1.0E+13 NO NO 133316 133316 133316 0
当然,存储仍在使用中,您仍然需要清除以释放它,它只是在数据字典中看起来更加一致。所以这看起来像是一个(非常小的)bug,最多可能。这可能与支持说明394442.1中提到的行为有关。上述查询为我的用户返回了0行。查询所有\u lob(而不是用户\u lob)时也返回了0行。无法查询dba_LOB:“ORA-00942:表或视图不存在”感谢您的详细解释和示例查询+1。很不错的。感谢您简洁(易读)的回答!
drop table t42;
table T42 dropped.
select object_name, object_type, status from user_objects
where object_type like 'LOB%';
no rows selected
select * from user_recyclebin;
OBJECT_NAME ORIGINAL_NAME OPERATION TYPE TS_NAME CREATETIME DROPTIME DROPSCN PARTITION_NAME CAN_UNDROP CAN_PURGE RELATED BASE_OBJECT PURGE_OBJECT SPACE
------------------------------ -------------------------------- --------- ------------------------- ------------------------------ ------------------- ------------------- ---------- -------------------------------- ---------- --------- ---------- ----------- ------------ ----------
BIN$5IUNXtWnUXLgQwEAAH9TlQ==$0 MY_CLOB_SEGMENT DROP LOB USERS 2013-08-22:08:36:41 2013-08-22:08:36:41 1.0E+13 NO NO 133316 133316 133316 0
BIN$5IUNXtWoUXLgQwEAAH9TlQ==$0 T42 DROP TABLE USERS 2013-08-22:08:36:41 2013-08-22:08:36:41 1.0E+13 YES YES 133316 133316 133316 0
SYS_IL0000133316C00001$$ SYS_IL0000133316C00001$$ DROP LOB INDEX USERS 2013-08-22:08:36:41 2013-08-22:08:36:41 1.0E+13 NO NO 133316 133316 133316 0