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5 Replies Latest reply: May 5, 2013 3:18 PM by Sergiusz Wolicki (Oracle) RSS

NLS_LENGTH_SEMANTICS = CHAR import is too slow

user632098 Newbie
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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:

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.


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