Oracle-L: RE: Import 8.1.6 to 9.2.0.1 weirdness

From: DENNIS WILLIAMS <DWILLIAMS_at_LIFETOUCH.COM>
Date: Thu, 15 May 2003 16:16:40 -0800
Message-ID: <F001.0059A40B.20030515161640@fatcity.com>

Karen - So . . . in the world of customer support we can mark this one down as "customer has a workaround". Just kidding.

I searched Metalink but didn't see anything obvious. You might run STATSPACK or your favorite method of examining wait statistics while the import is going just to see if you can spot anything that might cause the slowness.

Dennis Williams
DBA, 80%OCP, 100% DBA
Lifetouch, Inc.
dwilliams_at_lifetouch.com

-----Original Message-----
Sent: Thursday, May 15, 2003 6:48 PM
To: Multiple recipients of list ORACLE-L

Would anyone have any idea what might be going on with the following import situation?

I'm importing a 8.1.6 database into a 9.2 database. There are almost 400 tables and the import seems to chug along fine until I get to a table with a CLOB column in it. At that point, the import loads in anywhere between a few hundred and a few thousand rows of that table and then "hangs". I end up having to kill the import session and start over. Actually what has mostly happened is that I can't even simply restart but end up having to shutdown the database and restart it before I can continue (don't worry it's a new test box so all the ups and downs aren't an issue). Since I'm using commit=y and the tables involved all have unique keys, I simply have been restarting the import and letting it take off from there.

Here's my imp command:
imp id/pswd file=exp816.dmp commit=y ignore=y analyze=n buffer=16384 fromuser=user1 touser=user2

I've tried changing the buffer setting from 4K to 64K with no apparent effect. I've also tried various other parameter combinations other than those listed with no help. The command you see is what seems to work best.

The real weird thing is that if I just keep restarting the database and then restarting the import, the table will eventually load. For one table that had 30000 rows, I had to start the import and let it run until it hung, then shutdown the database and restart the import 10 times to get the full table to load. Once it loads, the import continues on just fine until it hits another table that has a CLOB datatype. Actually it goes one step further than just being a table with a CLOB, it's a table with a CLOB that's over 2K or so. There are a couple of tables with CLOB columns but the max size of the data stored in that column is relatively small. The tables that seem to have troubles have max size in the CLOB column of over 2K.

I just need to get this data loaded for test purposes so I can put up with the process for the moment, but I can't for the life of me figure out why it's acting this way. I've never seen behavior like this.

Does anybody have any ideas/suggestions or think of anything I may be missing somewhere that's causing this problem?

Many thanks,
Karen

Karen Morton
karen_at_morton-consulting.com

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Author: Karen Morton
INET: oracledba_at_morton-consulting.com

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Author: DENNIS WILLIAMS
INET: DWILLIAMS_at_LIFETOUCH.COM

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