DELETE then INSERT in collection - Order of executed SQL

[chetan chaphekar]

Hi,

 

I have two objects Client & Contact Person. Client object has collection of contact persons. When Client object is saved in update mode, it throws an error message ' Unique Key Violation',

Contact Person has a field CPCode which has Unique key constraint in Ms Sql. When i traced through sql profiler, I came to know that nhibernate fires Insert Statements first and then delete statements, because of this sql throws  ' Unique Key Violation' error.

 

Now my question is how can i change the sequence, i want nhibernate to fire delete statement first and then insert.

 

Please help

 

Regards

Chetan Chaphekar

[Oskar Berggren]

2011/12/6 chetan chaphekar <cchap...@gmail.com>:

One thing you can do is call Flush() on the ISession, or otherwise
trigger a flush after removal of the first element and before addition
of the new element. Not the most beautiful code though.

/Oskar

[Jason Meckley]

why not update the record rather than delete and insert?

[Ramon Smits]

Well that is probably his goal but code wise not really efficient. I often have the same problem which I usually solve by performing a .Clear() and then adding the items by creating new items based on a collection of dto items. These items are 99% of the time the exact same items value wise. Adding add/update/delete logic often is a shitload of code thus increased development time.

On Dec 7, 2011 6:29 PM, "Jason Meckley" <jasonm...@gmail.com> wrote:

why not update the record rather than delete and insert?

--
You received this message because you are subscribed to the Google Groups "nhusers" group.
To view this discussion on the web visit https://groups.google.com/d/msg/nhusers/-/81zueJdpjhkJ.
To post to this group, send email to nhu...@googlegroups.com.
To unsubscribe from this group, send email to nhusers+u...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/nhusers?hl=en.

[Maximilian Raditya]

On Tue, Dec 6, 2011 at 8:37 PM, chetan chaphekar <cchap...@gmail.com> wrote:

...

Now my question is how can i change the sequence, i want nhibernate to fire delete statement first and then insert.

...

 

 

I'd rather see the mapping and code that lead to such behavior.

 

 

 

 

Chetan Chaphekar

--

You received this message because you are subscribed to the Google Groups "nhusers" group.

To post to this group, send email to nhu...@googlegroups.com.
To unsubscribe from this group, send email to nhusers+u...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/nhusers?hl=en.

--
Regards,

Maximilian Haru Raditya

[TheCPUWizard]

Delete then Insert can lead to it’s own set of problems. From a “pure” standpoint, the deletes and inserts need to be sorted by time of occurrence, optimized to remove redundant operations, and then batched and fired.

 

I do not know of any way to do this with nHibernate, but there are some libraries that will do this directly at the ADO.Net level.

[chetan chaphekar]

Hi,

 

I think there is no easy way to do this. The only solution to this which mr Oskar has described, to Flush the session after removal of element before addition. but i still dont know why nhibernate has this behavour.

 

Thanks all of you for your help.

 

Regards

Chetan Chaphekar

[Oskar Berggren]

On the other hand, you speak of collections. According to the
reference, collection deletions should run before insertions.
http://nhforge.org/doc/nh/en/index.html#manipulatingdata-flushing

/Oskar

2011/12/8 chetan chaphekar <cchap...@gmail.com>: