NLS_LENGTH_SEMANTICS = CHAR import is too slow

From: <zigzagdna_at_yahoo.com>
Date: Sat, 4 May 2013 13:38:13 -0700 (PDT)
Message-ID: <1ef17e20-4b53-4c36-8227-849b4719d318_at_googlegroups.com>

I am converting a database from its current character set WE8ISO88591 to AL32UTF8 I am using NLS_LENGTH_SEMANTICS to CHAR so I do not have to increase column lengths.

I follow Oracle instructions:
144808.1
313175.1

Except import which takes way too long.

I took a full export of WE8ISO8859p1 Database and now importing it in AL32UTF8.

It is always difficult to prove where the slowness is coming from; but I think it has to do something with NLS_LENGTH_SEMANTICS. On the same server; if new database was in WE8ISO8859P1, a 5 million row table import took 2 hours; but in Al32UTF8 with NLS_LENGTH_SEMANTICS it is taking 1 day!!!

Any idea how to improve the performance of import. Received on Sat May 04 2013 - 22:38:13 CEST