Help: Index Question

Help: Index Question

Post by Robert Lobe » Fri, 04 Aug 2000 04:00:00



I have a file where attribute 1 is often null.  If I create an index on
this attribute (a1) will this system complain?  If not, I suppose d3
will create an index with a null item i.d.

Any help would be appreciated.

 
 
 

Help: Index Question

Post by Don Verhage » Fri, 04 Aug 2000 04:00:00


You should have no problem creating an index in which the attribute data is
null. And yes, it will create an index entry for a (null). (This way you can
select a1="" and it will take advantage of the index)

--
Donald Verhagen
Unidata 3.3.2, HP-UX 10.x
Software Development


Quote:> I have a file where attribute 1 is often null.  If I create an index on
> this attribute (a1) will this system complain?  If not, I suppose d3
> will create an index with a null item i.d.

> Any help would be appreciated.


 
 
 

Help: Index Question

Post by mvp.. » Mon, 07 Aug 2000 04:00:00


I program in Universe, and in that environment theres a key word that
is used to exclude the creation on a null index.
CREATE.INDEX filename fieldname NO.NULLS.  Maybe there is something
similar in D3?  Good luck.


> You should have no problem creating an index in which the attribute
data is
> null. And yes, it will create an index entry for a (null). (This way
you can
> select a1="" and it will take advantage of the index)

> --
> Donald Verhagen
> Unidata 3.3.2, HP-UX 10.x
> Software Development



> > I have a file where attribute 1 is often null.  If I create an
index on
> > this attribute (a1) will this system complain?  If not, I suppose d3
> > will create an index with a null item i.d.

> > Any help would be appreciated.

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