space in the temporary tablespace were largely used when create a tab

[signalsys]

I have created a table named "A".
And table "B" is on another database and its size is about 4G.
Now i want to insert into A with the content of table B using dblink and in order to use less undo segment,I use the following statements:

SQL> alter table A nologging;
SQL> insert /*+append*/ into A select * from B;

But during the insertion, I found that the usage of temporary tablespace was increasing rapidly.
For a table about 4G in size, it needs at least 4G temporary tablespace.

I want to know when table A is in nologging mode, Why it needs a lot of space in temporary tablespace during the insertion ?

 

[BocaBurger]

Sounds like a DB question, not an OS question.

BocaBurger
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