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From:Joerg Bruehe Date:January 7 2010 4:30pm
Subject:Re: table export in cron
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Hi Machiel, all!


machiel.richards wrote:
> Hi All
> 
> 	[[...]]
> 
> 	What the Oracle guys found was that some of the fields were blank even though the
> fields were configured as not nullable.
> 
> 	I found that where this is the case, the users entered a blank space which is then
> counted as a character and is thus not null.
> 
> 	This is causing all kinds of havoc for them as Oracle apparently still sees this as
> nulls.

In SQL, both an empty string "" and a string with just a blank " " are
well-defined values, different from the unknown NULL.

AFAIR, Oracle had a tradition of treating empty and/or blank strings as
NULL. I don't know whether that still holds, and whether it can be
influenced by some setting.

Which value would be used on the Oracle side for such fields? You could
always import into a stage table on the Oracle side which allows NULL,
then update to some non-NULL default value, then transfer into the final
one.


Jörg

-- 
Joerg Bruehe,  MySQL Build Team,  Joerg.Bruehe@stripped
Sun Microsystems GmbH,   Komturstraße 18a,   D-12099 Berlin
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Thread
table export in cronmachiel.richards6 Jan
  • Re: table export in cronGary Smith6 Jan
  • Re: table export in cronMikhail Berman6 Jan
    • Re: table export in cronsureshkumarilu6 Jan
Re: table export in cronMichael Dykman6 Jan
Re: table export in cronNicola Salvemini7 Jan
  • RE: table export in cronmachiel.richards7 Jan
    • Re: table export in cronJoerg Bruehe7 Jan
    • RE: table export in cronDan8 Jan