[V4MD] Object Pointers

[Ruslan Zasukhin]

On 8/7/04 9:23 PM, "Daniel Crowder" <daniel at monumental-i.com> wrote:

>> Yes of course.
>> 
>> Just set both ObjectPtr to have CASCADE deletion.
>> Then Valentina will a automatically delete records in Link table.
>> 
>>  
>> 
> Just to confirm: When the ObjectPtr field type is set to CASCADE the
> following would happen:
> 
> I have a product database record. It has a CATEGORY_ID that is an
> ObjectPTR (Cascade delete on) that points to a particular record in a
> CATEGORIES table. If I delete the category record it points to - the
> entire product record is deleted since it contains a cascade delete
> enabled ObjectPtr.

Yes.

Although before we have talk about Product, Media, LinkProductMedia
Tables.

Now you use also Category table

Just one advice.

We prefer to use name CATEGORE_PTR.
At least of end, sense of this field is *pointer*.

Yes, many RDBMS offer to use in both tables xxx_ID names.
I think this is not very logical.

 
> -CONVERSELY-
> 
> Using the same scenario as above: if the same ObjectPTR was set to
> restrict and NOT cascade. When I tried to delete that particular record
> in CATEGORIES it would have thrown an error because of the dependency
> and not delete the category record as a result.

Yes.

You must manually delete all child records,
Only after this you will be allowed delete

-- 
Best regards,
Ruslan Zasukhin      [ I feel the need...the need for speed ]
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e-mail: ruslan at paradigmasoft.com
web: http://www.paradigmasoft.com

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