How to: Define and Modify a Parameterized Row Filter for a Merge Article (Replication Transact-SQL Programming)
When creating table articles, you can use parameterized row filters. These filters use a WHERE clause to select the appropriate data to be published. Rather than specifying a literal value in the clause (as you do with a static row filter), you specify one or both of the following system functions: SUSER_SNAME and HOST_NAME. For more information, see Parameterized Row Filters. Parameterized row filters can be created and modified programmatically using replication stored procedures.
To define a parameterized row filter for an article in a merge publication
At the Publisher on the publication database, execute sp_addmergearticle (Transact-SQL). Specify @publication, a name for the article for @article, the table being published for @source_object, the WHERE clause that defines the parameterized filter for @subset_filterclause (not including WHERE), and one of the following values for @partition_options, which describes the type of partitioning that will result from the parameterized row filter:
0 - Filtering for the article either is static or does not yield a unique subset of data for each partition (an "overlapping" partition).
1 - Resulting partitions are overlapping, and updates made at the Subscriber cannot change the partition to which a row belongs.
2 - Filtering for the article yields nonoverlapping partitions, but multiple Subscribers can receive the same partition.
3 - Filtering for the article yields nonoverlapping partitions that are unique for each subscription.
To change a parameterized row filter for an article in a merge publication
At the Publisher on the publication database, execute sp_changemergearticle. Specify @publication, @article, a value of subset_filterclause for @property, the expression that defines the parameterized filter for @value (not including WHERE), and a value of 1 for both @force_invalidate_snapshot and @force_reinit_subscription.
If this change results in different partitioning behavior, then execute sp_changemergearticle again. Specify @publication, @article, a value of partition_options for @property, and the most appropriate partitioning option for @value, which can be one of the following:
0 - Filtering for the article either is static or does not yield a unique subset of data for each partition (an "overlapping" partition).
1 - Resulting partitions are overlapping, and updates made at the Subscriber cannot change the partition to which a row belongs.
2 - Filtering for the article yields nonoverlapping partitions, but multiple Subscribers can receive the same partition.
3 - Filtering for the article yields nonoverlapping partitions that are unique for each subscription.
Example
This example defines a group of articles in a merge publication where the articles are filtered with a series of join filters against the Employee table that is itself filtered using a parameterized row filter on the LoginID column. During synchronization, the value returned by the HOST_NAME function is overridden. For more information, see Overriding the HOST_NAME() Value in the topic Parameterized Row Filters.
-- To avoid storing the login and password in the script file, the value
-- is passed into SQLCMD as a scripting variable. For information about
-- how to use scripting variables on the command line and in SQL Server
-- Management Studio, see the "Executing Replication Scripts" section in
-- the topic "Programming Replication Using System Stored Procedures".
--Add a new merge publication.
DECLARE @publicationdb AS sysname;
DECLARE @publication AS sysname;
DECLARE @table1 AS sysname;
DECLARE @table2 AS sysname;
DECLARE @filter AS sysname;
DECLARE @schema_hr AS sysname;
DECLARE @schema_sales AS sysname;
SET @publicationdb = N'AdventureWorks2008R2';
SET @publication = N'AdvWorksSalesPersonMerge';
SET @table1 = N'Employee';
SET @table2 = N'SalesPerson';
SET @filter = N'SalesPerson_Employee';
SET @schema_hr = N'HumanResources';
SET @schema_sales = N'Sales';
USE [AdventureWorks2008R2];
-- Enable AdventureWorks2008R2 for merge replication.
EXEC sp_replicationdboption
@dbname = @publicationdb,
@optname = N'merge publish',
@value = N'true';
-- Create new merge publication with Subscriber requested snapshot
-- and using the default agent schedule.
EXEC sp_addmergepublication
@publication = @publication,
@description = N'Merge publication of AdventureWorks2008R2.',
@allow_subscriber_initiated_snapshot = N'true',
@publication_compatibility_level = N'90RTM';
-- Create a new snapshot job for the publication, using the default schedule.
-- Pass credentials at runtime using sqlcmd scripting variables.
EXEC sp_addpublication_snapshot
@publication = @publication,
@job_login = $(login),
@job_password = $(password);
-- Add an article for the Employee table,
-- which is horizontally partitioned using
-- a parameterized row filter.
EXEC sp_addmergearticle
@publication = @publication,
@article = @table1,
@source_owner = @schema_hr,
@source_object = @table1,
@type = N'table',
@description = 'contains employee information',
@subset_filterclause = N'[LoginID] = HOST_NAME()';
-- Add an article for the SalesPerson table,
-- which is partitioned based on a join filter.
EXEC sp_addmergearticle
@publication = @publication,
@article = @table2,
@source_owner = @schema_sales,
@source_object = @table2,
@type = N'table',
@description = 'contains salesperson information';
-- Add a join filter between the two articles.
EXEC sp_addmergefilter
@publication = @publication,
@article = @table1,
@filtername = @filter,
@join_articlename = @table2,
@join_filterclause = N'[Employee].[BusinessEntityID] = [SalesPerson].[SalesPersonID]',
@join_unique_key = 1,
@filter_type = 1;
GO
-- Start the agent job to generate the full snapshot for the publication.
-- The filtered data snapshot is generated automatically the first time
-- the subscription is synchronized.
DECLARE @publication AS sysname;
SET @publication = N'AdvWorksSalesPersonMerge';
EXEC sp_startpublication_snapshot
@publication = @publication;
GO