前天在业务库中导出完整库时,再导入到新库时发现部分表丢失。 看日志后分析是部分空表没有导出。查google知,11G中新特性,当表无数据时,不分配segment,以节省空间。而使用exp命令时,无Segment的表不会被导出。 解决方案: http://wenku.baidu.com/view/
前天在业务库中导出完整库时,再导入到新库时发现部分表丢失。
看日志后分析是部分空表没有导出。查google知,11G中新特性,当表无数据时,不分配segment,以节省空间。而使用exp命令时,无Segment的表不会被导出。
解决方案:
http://wenku.baidu.com/view/7beb56f57c1cfad6195fa702.html
采取第三种:
先执行如下语句得出空表:
<strong>select 'alter table '||table_name||' allocate extent;' from user_tables where num_rows=0;</strong>
然后将执行结果复制到另一个SQL窗口,并执行类似的语句:
ALTER TABLE COMJARREF ALLOCATE EXTENT; ALTER TABLE COMSTORE ALLOCATE EXTENT; ALTER TABLE DATASERVER ALLOCATE EXTENT; ALTER TABLE EIMP_COLUMNS ALLOCATE EXTENT; ALTER TABLE EIMP_TABLES ALLOCATE EXTENT; --...................................................................
然后再导出,OK!
值得注意的是:这样强制分配后,增加了200多个空表,导出文件从原来的101M变为102M,略有增加。
助人等于自助! 3w@live.cn

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