How to: Define and Modify a Join Filter Between Merge Articles (Replication Transact-SQL Programming)
Merge replication supports join filters, which are typically used in conjunction with parameterized filters to extend table partitioning to other related table articles. This topic shows a parameterized filter on a parent article with join filters between this article and related child articles. Join filters can be defined and modified programmatically using replication stored procedures.
To define a join filter to extend an article filter to related articles in a merge publication
Define the filtering for the article being joined to, which is also known as the parent article.
For an article filtered using a parameterized row filter, see How to: Define and Modify a Parameterized Row Filter for a Merge Article (Replication Transact-SQL Programming).
For an article filtered using a static row filter, see How to: Define and Modify a Static Row Filter (Replication Transact-SQL Programming).
At the Publisher on the publication database, execute sp_addmergearticle (Transact-SQL) to define one or more related articles, which are also known as child articles, for the publication. For more information, see How to: Define an Article (Replication Transact-SQL Programming).
At the Publisher on the publication database, execute sp_addmergefilter (Transact-SQL). Specify @publication, a unique name for this filter for @filtername, the name of the child article created in step 2 for @article, the name of the parent article being joined to for @join_articlename, and one of the following values for @join_unique_key:
0 - indicates a many-to-one or many-to-many join between the parent and child articles.
1 - indicates a one-to-one or one-to-many join between the parent and child articles.
This defines a join filter between the two articles.
Warning
Only set @join_unique_key to 1 if you have a constraint on the joining column in the underlying table for the parent article that guarantees uniqueness. If @join_unique_key is set to 1 incorrectly, non-convergence of data may occur.
Example
This example defines an article for a merge publication, where the SalesOrderDetail table article is filtered against the SalesOrderHeader table that is itself filtered using a static row filter. For more information, see How to: Define and Modify a Static Row Filter (Replication Transact-SQL Programming).
DECLARE @publication AS sysname;
DECLARE @table1 AS sysname;
DECLARE @table2 AS sysname;
DECLARE @table3 AS sysname;
DECLARE @salesschema AS sysname;
DECLARE @hrschema AS sysname;
DECLARE @filterclause AS nvarchar(1000);
SET @publication = N'AdvWorksSalesOrdersMerge';
SET @table1 = N'Employee';
SET @table2 = N'SalesOrderHeader';
SET @table3 = N'SalesOrderDetail';
SET @salesschema = N'Sales';
SET @hrschema = N'HumanResources';
SET @filterclause = N'Employee.LoginID = HOST_NAME()';
-- Add a filtered article for the Employee table.
EXEC sp_addmergearticle
@publication = @publication,
@article = @table1,
@source_object = @table1,
@type = N'table',
@source_owner = @hrschema,
@schema_option = 0x0004CF1,
@description = N'article for the Employee table',
@subset_filterclause = @filterclause;
-- Add an article for the SalesOrderHeader table that is filtered
-- based on Employee and horizontally filtered.
EXEC sp_addmergearticle
@publication = @publication,
@article = @table2,
@source_object = @table2,
@type = N'table',
@source_owner = @salesschema,
@vertical_partition = N'true',
@schema_option = 0x0034EF1,
@description = N'article for the SalesOrderDetail table';
-- Add an article for the SalesOrderDetail table that is filtered
-- based on SaledOrderHeader.
EXEC sp_addmergearticle
@publication = @publication,
@article = @table3,
@source_object = @table3,
@source_owner = @salesschema,
@description = 'article for the SalesOrderHeader table',
@identityrangemanagementoption = N'auto',
@pub_identity_range = 100000,
@identity_range = 100,
@threshold = 80,
@schema_option = 0x0004EF1;
-- Add all columns to the SalesOrderHeader article.
EXEC sp_mergearticlecolumn
@publication = @publication,
@article = @table2,
@force_invalidate_snapshot = 1,
@force_reinit_subscription = 1;
-- Remove the credit card Approval Code column.
EXEC sp_mergearticlecolumn
@publication = @publication,
@article = @table2,
@column = N'CreditCardApprovalCode',
@operation = N'drop',
@force_invalidate_snapshot = 1,
@force_reinit_subscription = 1;
-- Add a merge join filter between Employee and SalesOrderHeader.
EXEC sp_addmergefilter
@publication = @publication,
@article = @table2,
@filtername = N'SalesOrderHeader_Employee',
@join_articlename = @table1,
@join_filterclause = N'Employee.EmployeeID = SalesOrderHeader.SalesPersonID',
@join_unique_key = 1,
@filter_type = 1,
@force_invalidate_snapshot = 1,
@force_reinit_subscription = 1;
-- Add a merge join filter between SalesOrderHeader and SalesOrderDetail.
EXEC sp_addmergefilter
@publication = @publication,
@article = @table3,
@filtername = N'SalesOrderDetail_SalesOrderHeader',
@join_articlename = @table2,
@join_filterclause = N'SalesOrderHeader.SalesOrderID = SalesOrderDetail.SalesOrderID',
@join_unique_key = 1,
@filter_type = 1,
@force_invalidate_snapshot = 1,
@force_reinit_subscription = 1;
GO
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 value of HOST_NAME in the LoginID column. For more information, see How to: Define and Modify a Parameterized Row Filter for a Merge Article (Replication Transact-SQL Programming).
-- 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'AdventureWorks';
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 [AdventureWorks];
-- Enable AdventureWorks 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 AdventureWorks.',
@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].[EmployeeID] = [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