Re: Insert without redo log

Inserts into temporary table generate rollback, and the rollback is covered by redo, so an insert into a temporary table does results in redo - albeit less than that required for a normal table.

You can do direct mode inserts to a GTT, but the table has to be 'on commit preserve' because you need to issue a COMMIT before you can select the rows back (standard
feature of direct inserts).

Just, to emphasise you point about GTTs
being private, you can't (usefully) SQL*Load into a GTT, as the data disappears the moment the SQL*Load session ends.

--
Jonathan Lewis
Yet another Oracle-related web site:  http://www.jlcomp.demon.co.uk

Practical Oracle 8i:  Building Efficient Databases
Publishers:  Addison-Wesley

Reviews at: http://www.jlcomp.demon.co.uk/book_rev.html



Howard J. Rogers wrote in message ...


>

>Also in 8i, there is now the concept of a global temporary table, and DMLs

>on them do not generate redo under any circumstances.  It is possible you

>could therefore contemplate loading into a temporary table first,then using

>an 'insert into blah select * from temptable' to get the data into the main

>table -that's a direct insert, and would respect a nologging attribute.

>

>I have not, however, ever tried doing a direct insert using a temporary

>table as the source, so I can't guarantee it would work (and in any case it

>needs 8i).  If you *do* have 8i, and want to try it out, remember that

>temporary tables are private to a session, and retain data only after a

>commit if you create them with the 'on commit preserve rows' construct.

>They are also instantly cleared out when the session ends.

>