shrink space 的整个过程就是在做delete和insert

yu85910

不错 不错

zhangzongjun

不错的试验，支持~

lsfredhat

很经典

simonwen

不错， 经典

qilin_sun

钻研的精神太可嘉了，要好好学习。

windly0721

CarryYang

Such testing could be performed by using Oracle log dump utility， e.g.

#1） CREATE TABLE TEST_SHRINK AS SELECT NAME,OBJ# FROM SYS.OBJ$;

#2)   ALTER TABLE TEST_SHRINK ENABLE ROW MOVEMENT;

#3)   SQL> SELECT COUNT(*) FROM TEST_SHRINK;

  COUNT(*)
----------
     69196

#4)   DELETE FROM TEST_SHRINK WHERE ROWNUM < 69194;
         COMMIT;

#5)   ALTER SYSTEM SWITCH LOGFILE;

#6)   ALTER TABLE TEST_SHRINK SHRINK SPACE;

#7)   DUMP LOG FILE - ALTER SYSTEM DUMP LOGFILE 'C:\ORACLE\PRODUCT\ORADATA\O11RDB\REDO03.LOG';

#8)   Open the trace file, and you can find the following redo records sequence:

a) OP:5.2(transaction slot) - OP:5.1(redo opeartion on undo block) - OP:11.3 (redo opearation on data block - delete op)

b) OP:5.1 - OP:11.2 (insert operation)

repeat a) and b) for each row.


F.Y.I.

nirvanv

学习了

ysping

受教了

wxhoracle

good