Does the compress = y parameter in EXP change the initial value in imp?

Example of the change in the initial value when the parameter compress = y in EXP causes imp: Import/Export version, platform: 11.2, windows import/export version, platform: 10.2, linux 1. create a test table: [SQL] SQL> conn scott/xyc is connected. SQL> create table test_c as select * from sys. dba_objects; the table has been created. 2. view the initial size of the export warehouse table test_c [SQL] SQL> set pagesize 0 SQL> set long 20000000000 SP2-0268: invalid long option number 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, "LAS T_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 BUF FER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "USERS", you can see that the initial of the table test_c in the export database is 655363. view the space occupied by the test-c table [SQL] SQL> select segment_name, bytes from user_segments where segment_name = 'test _ C '; SEGMENT_NAME BYTES ------------------------------ ---------- TEST_C 9437184 you can see that the table test_c occupies 94371844 space. export table test_c [plain] [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) 1982,200 5, 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. import table test_c [SQL] [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) 1982,200 5, 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. check the initial value size of TABLE test_c in the import/export database [SQL] 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 )) PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 nocompress logging storage (INITIAL 9437184 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 freelist groups 1 BUFFER_POOL DEFAULT) TABLESPACE "USERS" shows that the initial value of test_c in the export and export tables is 9437184, which is equal to the space occupied by test_c in the export and export tables. This indicates that compress = y in EXP causes the initial value change in imp.