关于插入数据与HWM的问题
For inserting data directly and indirectly, we'll find different result of HWM:
i.e :
SQL> truncate table a2;
SQL> alter system dump datafile 6 block 12003; -- 12003 (only three block for segment header)
SQL> insert into a2 select * from a1; (indirectly)
SQL> alter system dump datafile 6 block 12003; -- 12009 --- ?? 12009 how to choose the block to be used?
SQL> truncate table a2;
SQL> insert /*+ append */ into a2 select * from a1; (directly)
SQL> alter system dump datafile 6 block 12003; -- 12004 --- ?? Does this means the insert data only use a block above 12003?
SQL> commit;
SQL> alter system dump datafile 6 block 12003; -- 12005 --- ?? What's the inner process?
Could you please let me know the inner processes for the three incarnations? Thanks in advance for your helpful answer!
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