Of course it doesn't, and it will never have! Cascade actions are performed
by NHibernate, not at the database level!
RP
On Thursday, May 15, 2014 4:50:11 PM UTC+1, Dawid Ciecierski wrote:
>
> Ricardo, thanks for your help but if you look closer at the resulting
> database (and/or the exported schema) you'll notice that the foreign key
> relationship has NO ACTION set for the ON DELETE event in the foreign key
> constraint. This works fine when executing everything via NHibernate's
> entity management methods, but fails when a simple DELETE is issued against
> the database.
>
> Dawid
>
> On Thursday, May 15, 2014 12:58:12 PM UTC+2, Ricardo Peres wrote:
>>
>> I have a similar mapping - Post and Tag - where one Post can have several
>> tags, which are just strings (sorry, don't have time to change it):
>>
>> this.Set(x => x.Tags, x =>
>> {
>> x.Key(y =>
>> {
>> y.Column("post_id");
>> y.NotNullable(true);
>> });
>> x.Cascade(Cascade.All);
>> x.Lazy(CollectionLazy.NoLazy);
>> x.Fetch(CollectionFetchMode.Join);
>> x.Table("tag");
>> }, x =>
>> {
>> x.Element(y =>
>> {
>> y.Column("tag");
>> y.Length(20);
>> y.NotNullable(true);
>> y.Unique(true);
>> });
>> });
>>
>>
>> I am using set instead of bag, this is generally better, and in your
>> case, I imagine you don't want duplicate values stored.
>> See if this works!
>>
>> RP
>>
>> On Thursday, May 15, 2014 11:31:13 AM UTC+1, Dawid Ciecierski wrote:
>>>
>>> Hello,
>>>
>>> Let me start by asking the moderator to please look at my previous post
>>> sent around Friday (May 9), as it went into much greater detail as well as
>>> linked to a sample project but for some reason was not approved... Would be
>>> grateful if you could look at it again as I spend a good several minutes
>>> describing what I'm trying to accomplish as best I could.
>>>
>>> Also wanted to add that this is a sister post to one on the developers
>>> group<https://groups.google.com/forum/#!topic/nhibernate-development/UTbygrpFz04>,
>>>
>>> in which I tried to go into more technical aspects of this issue, but was
>>> still directed to this group :-)
>>>
>>> Without further ado thou. What I have is frequently updated and delete-d
>>> entity that is just a view on a more complex business domain. Each entity
>>> in this "view" has a child collection of simple strings (think tags).
>>> Because of the DELETE FROM [TableName] we regularly execute, I'd like
>>> to mark the foreign key relationship as ON DELETE CASCADE. Right now I
>>> do so manually but only because I've found no way to coerce NHibernate into
>>> seeing the relationship the same way. Ultimately I'd like to find a way to
>>> do so as the whole database is frequently rebuilt from scratch by
>>> SchemaExport and doing manual updates to multiple foreign key relationships
>>> is time-consuming. Below is a simple class with its mapping demonstrating
>>> the use case:
>>>
>>> public class Photo
>>> {
>>> public int Id { get; set; }
>>> public string Name { get; set; }
>>> public IList<string> Tags { get; set; }
>>>
>>> public Photo()
>>> {
>>> Tags = new List<string>();
>>> }
>>> }
>>>
>>> public class PhotoMap : ClassMapping<Photo>
>>> {
>>> public PhotoMap()
>>> {
>>> Lazy(false);
>>> Id(p => p.Id);
>>> Property(p => p.Name);
>>> Bag(
>>> p => p.Tags,
>>> collectionMapping: collectionMapping =>
>>> {
>>> //collectionMapping.Inverse(true);
>>> collectionMapping.Lazy(CollectionLazy.NoLazy);
>>> collectionMapping.Cascade(Cascade.All | Cascade.DeleteOrphans);
>>> },
>>> mapping: mapping =>
>>> {
>>> //mapping.OneToMany(); // NH does not like this
>>> mapping.Element(e => e.Column("tag_value"));
>>> });
>>> }
>>> }
>>>
>>> When I uncomment the mapping.OneToMany line NHibernate tells me that
>>> there is an unmapped entity System.String, so clearly I'm going against its
>>> way of thinking (and on the developers' group Ricardo confirmed that
>>> one-to-many is for entities only). Will be grateful for any advice on how I
>>> can make it work.
>>>
>>> Best regards,
>>> Dawid Ciecierski
>>>
>>> Ps. I've prepared a sample project that does not make actual database
>>> calls which I can link to, but will refrain myself from doing so just in
>>> case linking outside of Google Groups automatically puts my post in the
>>> moderator's trash.
>>>
>>
--
You received this message because you are subscribed to the Google Groups
"nhusers" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/nhusers.
For more options, visit https://groups.google.com/d/optout.
