Re: parallel import

"Tatireddy, Shrinivas (MED, Keane)" wrote:
>
> Hi lists,
>
> Is there a parallel import into table / schema . ?

no.

> (The table/tables have primary keys as well as indexes )
> (need to finish the import in less time, than traditional import )
> Thnx in advance

> srinivas

you did not specify a version of Oracle server. bad practice.

if the table was created as having a parallel degree, then the create statement in the dump file should likely reflect that - however - if the data is in a single dump file, the import will likely be limited by the read rate of the dump and by the fact that the data is being read, parsed and executed in a non-direct fashion. create a dump file for one table that has a parallel degree, import it with a show=Y and examine the DDL/DML.

Kirti posted tips for import/export that was quite good. I would suggest examining the list archives for postings by Kirti with "export" and "import".
Unfortunately, I don't have my Performance 101 book here at home - I think he covered this in there also.

Import is import.exe - the only other ways are to unload the data (by various methods) and reload via SQL Loader, or copy across a db_link (not recommended).

0. C:\> imp help=y

1. can you break up the export into multiple schemas? (owner=schema1) that is the easiest way to parallelize the import, where each schema gets it own tablespace with datafiles on independent storage volumes, reading from a dump file on independent storage volumes.
2. can you break the export up by table (owner=schema1, tables = (table_name1,...,table_namen) and execute those simultaneously?
3. don't have the indexes created by import - alter the DDL used to create them such that they are created with a parallel degree that you desire. This could be accomplished with the INDEXFILE parameter. Also create them as nologging.
4. only have a small number of large rollback segments online, as you can't specify a rollback segment to be used during import.
5. what are you wait events during import
   • redo and archived redo log?
   • rollback segment allocation?
   • checkpoints?
   • recursive sql?
6. are your extents properly sized? are you using locally managed tablespaces

check out AskTom at ttp://asktom.oracle.com e.g.: http://asktom.oracle.com/pls/ask/f?p=4950:8:317629::NO::F4950_P8_DISPLAYID,F4950_P8_CRITERIA:1574966483719,%7Bimport%7D

hth,

Paul

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Paul Drake
  INET: paled_at_home.com

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).