Oracle 11g exp Default empty table does not export cause and workaround

In oracle11g, when each table is initially created, the default is to not allocate extents to this object.

When the data is first inserted, the corresponding extents are assigned.

The corresponding control parameter is Deferred_segment_creation=true

If you want to maintain a property that is consistent with the lower version, you can set this parameter value to Flase

Alter system set DEFERRED_SEGMENT_CREATION=FALSE Scope=both;

In the subsequent creation of the new table, the section is assigned by default.

If the parameter value is set to True, the corresponding segment is not allocated even if you specify a specific storage parameter to get the initial segment size when the table is created.

eg

CREATE TABLE A_allocat_extent

(

Userno number,

Username VARCHAR2 (CHAR)

)

Tablespace USERS

Pctfree 10

Initrans 1

Maxtrans 255

Storage

(

Initial 64K

Next 1M

Minextents 1

Maxextents Unlimited

);

Sql> SELECT * from user_extents t where T.segment_name = ' a_allocat_extent ';

No rows selected

After setting the parameter value to False, you need to add a section to the table without the allocated section.

To get a table name without a partition:

Select table_name from User_tables

Minus

Select Segment_name from User_segments

The partition statement is then executed for allocation:

ALTER TABLE A_allocat_extent allocate EXTENT (size 8K); --size own definition

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Oracle 11g exp Default empty table does not export cause and workaround