How to update conflict resolver when upgrading from SQL-Server 2005 to SQL-Server 2008 We have recently upgraded from SQL Server 2005 to SQL Server 2008 (R2, SP1). This upgrade included some publications, where all tables are published with a default conflict resolver based on the "later wins" principle.

As you all know, once a table is published with a conflict resolver, the same conflict resolver must be used in all later publications using this table. Fair enough, but, when adding previously published tables to new publications, and specifying the very same conflict resolver to be used for this table, , we are getting an error message: 

use [myDb]
exec sp_addmergearticle 
    @publication = N'myDb_Pub', 
    @article = N'Tbl_blablabla', 
    @source_owner = N'dbo', 
    @source_object = N'Tbl_blablabla', 
    @type = N'table', 
    @description = N'', 
    @creation_script = N'', 
    @pre_creation_cmd = N'drop', 
    @schema_option = 0x000000000C034FD1, 
    @identityrangemanagementoption = N'none', 
    @destination_owner = N'dbo', 
    @force_reinit_subscription = 1, 
    @column_tracking = N'false', 
    @article_resolver = N'Microsoft SQL Server DATETIME (Later Wins) Conflict Resolver', 
    @subset_filterclause = N'', 
    @resolver_info = N'ddmaj', 
    @vertical_partition = N'false', 
    @verify_resolver_signature = 0, 
    @allow_interactive_resolver = N'false', 
    @fast_multicol_updateproc = N'true', 
    @check_permissions = 0, 
    @subscriber_upload_options = 0, 
    @delete_tracking = N'true', 
    @compensate_for_errors = N'false', 
    @stream_blob_columns = N'false', 
    @partition_options = 0
GO


And this is the error we get:

The article '...' already exists in another publication with a different article resolver.


By trying to understand how the same conflict resolver is not considered by the machine as 'the same conflict resolver', I discovered that there were two conflict resolvers with the same name, different versions, in the registry:

the 2005 version: 


file ssrmax.dll, 
version 2005.90.4035.0, 
cls_id D604B4B5-686B-4304-9613-C4F82B527B10


the 2008 version:


file ssrmax.dll, 
version 2009.100.2500.0, 
cls_id 77209412-47CF-49AF-A347-DCF7EE481277


And I checked that our 2008 server is considering the second one as the 'available custom resolver' (I got this by running sp_enumcustomresolvers). The problem is that both references are available in the registry, so I guess that old publications do refer to the 2005 version, while new publications try to refere to the 2008 version, which is indeed different from the previous one.

So the question is: how can I have the server consider only one of these 2 versions, and this (of course) without having to drop and recreate the existing publications (which would turn our life into hell for the next 2 weeks).
Well .. so nobody got an answer. But I think I (finally) got it. Guess what... it is somewhere in the metamodel (as usual)!


When adding an item to the subscription, the new conflict resolver references to be used by the stored procedure come from the [distribution].[MSmerge_articleresolver] table
But, for existing subscriptions, previous conflict resolver references are stored in the system tables of the publishing database, ie [sysmergearticles], [sysmergeextendedarticlesview], and [sysmergepartitioninfoview]


So we have on one side an item initialy published with SQLSERVER 2005, where the publication references the 2005 conflict resolver, as per the publishing database metamodel. On the other side, the machine will attempt to add the same item to a new publication, this time with a default reference to the conflict resolver available in the distibution database, which is indeed different from the 2005 one ....  

To illustrate this, you can check the following

USE distribution
go
SELECT article_resolver, resolver_clsid
  FROM [MSmerge_articleresolver] WHERE article_resolver like '%Later Wins%'
  GO


Then, 

USE myPublicationDatabase
go
SELECT article_resolver, resolver_clsid
  FROM [sysmergearticles] WHERE article_resolver like '%Later Wins%'
  GO
 SELECT article_resolver, resolver_clsid
  FROM [sysmergeextendedarticlesview] WHERE article_resolver like '%Later Wins%'
  GO
 SELECT article_resolver, resolver_clsid
  FROM [sysmergepartitioninfoview] WHERE article_resolver like '%Later Wins%'
  GO  


So it seems that I should update either the references in the distribution database or the references in the publication database. Let's give it  a try!