Q: SQLLDR and existing records/Unique constraint which allow nulls?
From: Major <lievonen_at_jyu.fi.HALOOOOOOOO>
Date: Wed, 29 Aug 2001 07:53:08 GMT
Message-ID: <Eb1j7.118$3h3.4423_at_read2.inet.fi>
Hello.
Date: Wed, 29 Aug 2001 07:53:08 GMT
Message-ID: <Eb1j7.118$3h3.4423_at_read2.inet.fi>
Hello.
[Quoted] [Quoted] I have table which have primary key (sequence).
I have one varchar2 field in source file and table,
whose should be "unique".
So when I uploadin to database, I should check
that is this value in the table and if not, load it and
if it is in table, skip record.
How I can do this?
[Quoted] [Quoted] I think so that I cannot define unique constraint to table because this field can have null -value (source files havenīt null values). Is this true that unique constraint doen't allow null values? [Quoted] Is there any other constraits which is like unique but allow nulls? I can build check constraint with "not in (select xx from table)" but this is so slow...
Regards Major Received on Wed Aug 29 2001 - 09:53:08 CEST