Perform an experiment where initial is larger than uniform size multiplied by minextents, and summarize the distribution rule of initial extent, minextentsinitial

Perform an experiment where initial is larger than uniform size multiplied by minextents, and summarize the distribution rule of initial extent, minextentsinitial

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Perform an experiment where initial extent is larger than UNIFORM size multiplied by MINEXTENTS. Summarizes the distribution rules of initial extent.

Connected to:Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit ProductionWith the Partitioning, OLAP, Data Mining and Real Application Testing optionsSQL> alter system set deferred_segment_creation=false;System altered.SQL> show parameter deferNAME                                 TYPE        VALUE------------------------------------ ----------- ------------------------------deferred_segment_creation            boolean     FALSESQL> create tablespace test_uni_sz_1m   2  datafile '/u01/app/oracle/oradata/test/test_uni_sz_1m_01.dbf' size 200m  3  extent management local uniform size 1m;Tablespace created.SQL> create table test_tab_3 (col1 varchar2(2)) tablespace test_uni_sz_1m storage(initial 10m minextents 3); Table created.SQL> select bytes from dba_extents where segment_name = 'TEST_TAB_3' and owner = 'SCOTT';     BYTES----------   1048576   1048576   1048576   1048576   1048576   1048576   1048576   1048576   1048576   1048576   1048576     BYTES----------   104857612 rows selected.SQL> show user    USER is "SCOTT"SQL> 

The result is 12 extents with a size of 1 M (I .e., uniform size) allocated.

It seems that the first 10 1 M correspond to the first minextents, and the second and third 1 M correspond to the second and third minextents.