Oracle 11g exp Export Table not complete

Today on the oracle11g with the EXP command to export when encountered a strange phenomenon, no data table exp is always not out, the query found this is a new feature of Oracle 11g, when the table has no data, do not allocate segment, to save space. When using the EXP command, tables without segment are not exported.

Workaround:

Select ' ALTER TABLE ' | | table_name| | ' allocate extent; ' from User_tables where num_rows=0;

The results are as follows:

Alter table XXX allocate extent;

Find out all the results and re-execute them in Sqlplus.

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deferred_segment_creation Parameters:

Property	Description
Parameter type	Boolean
default value	true
< P>modifiable	alter SESSION ,? alter SYSTEM
Range of values	true | False
Basic	No

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deferred_segment_creation ?specifies The semantics of deferred segment creation. If set to? True

before creating a set of tables, if it is known, a significant number of them would not being populated, then consider Setting this parameter to? true. This saves disk space and minimizes install time.

fromOracle 11g Release 2start, add adeferred_segment_creationparameter, the default value istruerepresents the time when the newly created table is assignedextent, the distribution is only started when the data is insertedextent. In a regular environment, the tables are not immediately assigned because they are createdextent, save space, reduce creation time, so can improve efficiency.

You can use the following command to disable this Feature:

alter system set DEFERRED_SEGMENT_CREATION=FALSE;

This only affects the tables that are created later, and does not affect the tables created between them.

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Ref

http://dbaora.com/deferred-segment-creation-on-demand-oracle-database-11g-release-2-11-2/

http://blog.csdn.net/tianlesoftware/article/details/6603608

Http://stackoverflow.com/questions/18924704/how-to-export-empty-tables-in-oracle

Http://www.cnblogs.com/downmoon/archive/2012/12/03/2799864.html

Oracle 11g exp Export Table not complete