日期:2014-05-16 浏览次数:20417 次
EXP中compress=y是否导致imp时initial值的变化
举例证明:
导出库版本、平台:11.2,windows
导入库版本、平台:10.2,linux
1.创建测试表:
SQL> conn scott/xyc 已连接。 SQL> create table test_c as select * from sys.dba_objects; 表已创建。
2.查看导出库中表test_c的initial大小
SQL> set pagesize 0 SQL> set long 20000000000 SP2-0268: long 选项的编号无效 SQL> set long 2000000 SQL> select dbms_metadata.get_ddl('TABLE','TEST_C','SCOTT') from dual; CREATE TABLE "SCOTT"."TEST_C" ( "OWNER" VARCHAR2(30), "OBJECT_NAME" VARCHAR2(128), "SUBOBJECT_NAME" VARCHAR2(30), "OBJECT_ID" NUMBER, "DATA_OBJECT_ID" NUMBER, "OBJECT_TYPE" VARCHAR2(19), "CREATED" DATE, "LAST_DDL_TIME" DATE, "TIMESTAMP" VARCHAR2(19), "STATUS" VARCHAR2(7), "TEMPORARY" VARCHAR2(1), "GENERATED" VARCHAR2(1), "SECONDARY" VARCHAR2(1), "NAMESPACE" NUMBER, "EDITION_NAME" VARCHAR2(30) ) SEGMENT CREATION IMMEDIATE PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "USERS"
可以看到导出库中表test_c的initial为65536
3.查看表test-c占用空间
SQL> select segment_name, bytes from user_segments where segment_name = 'TEST_C'; SEGMENT_NAME BYTES ------------------------------ ---------- TEST_C 9437184
可以看到导出库中表test_c占用空间为9437184
4.导出表test_c
[oracle@s1 ~]$ exp scott/xyc@orcl compress=y file=/home/oracle/exptab_test_c.dmp tables=test_c; Export: Release 10.2.0.1.0 - Production on Fri Apr 5 05:44:54 2013 Copyright (c) 1982, 2005, Oracle. All rights reserved. Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production With the Partitioning, OLAP, Data Mining and Real Application Testing options Export done in US7ASCII character set and AL16UTF16 NCHAR character set server uses AL32UTF8 character set (possible charset conversion) About to export specified tables via Conventional Path ... . . exporting table TEST_C 73167 rows exported Export terminated successfully without warnings.
5.导入表test_c
[oracle@s1 ~]$ imp scott/xyc file=/home/oracle/exptab_test_c.dmp tables=test_c Import: Release 10.2.0.1.0 - Production on Fri Apr 5 05:47:23 2013 Copyright (c) 1982, 2005, Oracle. All rights reserved. Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production With the Partitioning, OLAP and Data Mining options Export file created by EXPORT:V10.02.01 via conventional path import done in US7ASCII character set and AL16UTF16 NCHAR character set import server uses WE8ISO8859P1 character set (possible charset conversion) . importing SCOTT's objects into SCOTT . importing SCOTT's objects into SCOTT . . importing table "TEST_C" 73167 rows imported Import terminated successfully without warnings.
6.在导入库查看test_c表的initial值大小
SQL> select dbms_metadata.get_ddl('TABLE','TEST_C','SCOTT') from dual; CREATE TABLE "SCOTT"."TEST_C" ( "OWNER" VARCHAR2(30), "OBJECT_NAME" VARCHAR2(128), "SUBOBJECT_NAME" VARCHAR2(30), "OBJECT_ID" NUMBER, &qu