Null Value Stored for Date e TimeStamp

Started by Fernando Ferreiraabout 21 years ago2 messageshackers
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#1Fernando Ferreira
lfernando@pop.com.br

Hi,

I would like know about the value stored for null value for fields date
and timestamp.

Sample
SQL Server 1753/01/01
Oracle 0001/01/01
Informix 1899/01/01
Visual Foxpro DBF 1899/12/30

I used a tool for migrate database and informed the nullvalues for date
fields in source and destine database.

I 'm convert DBF to PostgreSQL and the values for null dates from DBF
are stored as 1899/12/30 in PostgreSQL tables.

Thanks

Fernando Ferreira

#2Tom Lane
tgl@sss.pgh.pa.us
In reply to: Fernando Ferreira (#1)
Re: Null Value Stored for Date e TimeStamp

Fernando Ferreira <lfernando@pop.com.br> writes:

I would like know about the value stored for null value for fields date
and timestamp.

There isn't any; we don't store anything at all for a null.

I don't think those other DBs you mention equate a null to some
particular randomly chosen date, either. You might be dealing with
some broken application software that uses such a thing as a way to
avoid dealing with true nulls ...

regards, tom lane