How to: Configure Nonpartitioned, Bidirectional, Transactional Replication (Replication Transact-SQL Programming)

Bidirectional transactional replication is a specific transactional replication topology that allows two servers to exchange changes with each other: each server publishes data and then subscribes to a publication with the same data from the other server.

This topology is also supported by peer-to-peer transactional replication, but bidirectional replication can provide improved performance. For more information, see Peer-to-Peer Transactional Replication.

To configure a nonpartitioned, bidirectional transactional replication topology between databases on two servers

1. Enable each server as a Publisher and Distributor. For more information, see How to: Configure Publishing and Distribution (Replication Transact-SQL Programming).

2. At each server on the database to be bidirectionally replicated, execute sp_replicationdboption (Transact-SQL). Specify the database name for @dbname, a value of publish for @optname, and a value of true for @value.

3. At each server on the database to be bidirectionally replicated, execute sp_addpublication (Transact-SQL). Specify a name for the publication for @publication.

4. At each server on the database to be bidirectionally replicated, execute sp_addarticle (Transact-SQL). Specify the following parameters:

   • @article - the name of the article.

   • @publication - the publication name from step 3.

   • @source_object - the name of the published table.

   • @destination_table - the name of the equivalent table in the database on the other server.

   • @schema_option - ensure that the value 0x02 is not set.

     Note

     When a value of 0x02 is not set, an & (Bitwise AND) (Transact-SQL) operation on @schema_option will return a value of 0. To perform this operation, you must convert the binary values to int.

   • @ins_cmd - a value of CALL sp_ins_destination_article_name.

   • @upd_cmd - a value of SCALL sp_upd_destination_article_name.

   • @del_cmd - a value of CALL sp_del_destination_article_name.

     Note

     These values represent the default call formats. Other call formats can be used.

5. Repeat step 4 for each article in the bidirectional publication.

6. At each server on the database to be bidirectionally replicated, execute sp_addsubscription (Transact-SQL). Specify the following parameters:

   • @publication - the name of the publication from step 3.

   • @subscriber - the name of the other server.

   • @destination_db - the name of the database at the other server.

   • @sync_type - a value of none.

   • @status - a value of active.

   • @loopback_detection - a value of true.

7. At each server on the database to be bidirectionally replicated, execute sp_addpushsubscription_agent (Transact-SQL). Specify the following parameters:

   • @publication - the name of the publication from step 3.

   • @subscriber - the name of the other server.

   • @subscriber_db - the name of the database at the other server.

   • @job_login - the Microsoft Windows credentials under which the Distribution Agent at the Distributor runs.

   • @job_password - the password for the Windows credentials under which the Distribution Agent at the Distributor runs.

     Security Note
     When possible, prompt users to enter security credentials at runtime. If you must store credentials in a script file, you must secure the file to prevent unauthorized access.

8. Using the names specified in step 4, create custom stored procedures to handle conflicts and do inserts, updates, and deletes. For more information, see How to: Set the Propagation Method for Data Changes to Transactional Articles (Replication Transact-SQL Programming).

Example

This example creates two test databases on the same server and then configures nonpartitioned, bidirectional, transactional replication between them.

-- This script uses sqlcmd scripting variables. They are in the form
-- $(MyVariable). 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".

USE master;
GO

-- Create the test databases if they do not exist.
IF NOT EXISTS(SELECT * FROM sys.databases WHERE name = 'test1')
    CREATE DATABASE test1;

IF NOT EXISTS(SELECT * FROM sys.databases WHERE name = 'test2')
    CREATE DATABASE test2;
GO

-- Enable the server as a Distributor, if not already done.
DECLARE @distributor AS sysname;
EXEC sp_helpdistributor @distributor = @distributor OUTPUT;
IF @distributor <> @@SERVERNAME
BEGIN
    EXEC master..sp_adddistributor @distributor = @@SERVERNAME;
    EXEC master..sp_adddistributiondb @database= 'distribution';
END
GO

-- Enable the server as a Publisher, if not already done.
IF NOT EXISTS (SELECT * FROM msdb..MSdistpublishers WHERE name = @@SERVERNAME)
    EXEC master..sp_adddistpublisher 
        @publisher = @@SERVERNAME, 
        @distribution_db = 'distribution', 
        @working_directory = 'C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\repldata'; 
GO

-- Enable the databases for transactional publishing.
EXEC sp_replicationdboption N'test1', N'publish', true;
EXEC sp_replicationdboption N'test2', N'publish', true;
GO

-- Create a table in test1 and populate with 10 rows.
USE test1;
GO

IF EXISTS (SELECT * FROM sysobjects WHERE name LIKE 'two_way_test1')
    DROP TABLE two_way_test1;
GO

CREATE TABLE two_way_test1
(pkcol int primary key not null,
 intcol int,
 charcol char(100),
 datecol datetime
);
GO

INSERT INTO two_way_test1 VALUES (1, 10, 'row1', GETDATE());
INSERT INTO two_way_test1 VALUES (2, 20, 'row2', GETDATE());
INSERT INTO two_way_test1 VALUES (3, 30, 'row3', GETDATE());
INSERT INTO two_way_test1 VALUES (4, 40, 'row4', GETDATE());
INSERT INTO two_way_test1 VALUES (5, 50, 'row5', GETDATE());
INSERT INTO two_way_test1 VALUES (6, 60, 'row6', GETDATE());
INSERT INTO two_way_test1 VALUES (7, 70, 'row7', GETDATE());
INSERT INTO two_way_test1 VALUES (8, 80, 'row8', GETDATE());
INSERT INTO two_way_test1 VALUES (9, 90, 'row9', GETDATE());
INSERT INTO two_way_test1 VALUES (10, 100, 'row10', GETDATE());
GO

-- Create a table in test2 and populate with 10 rows
USE test2;
GO

IF EXISTS (SELECT * FROM sysobjects WHERE name LIKE 'two_way_test2')
    DROP TABLE two_way_test2;
GO

CREATE TABLE two_way_test2
(pkcol int primary key not null,
 intcol int,
 charcol char(100),
 datecol datetime
);
GO

INSERT INTO two_way_test2 VALUES (1, 10, 'row1', GETDATE());
INSERT INTO two_way_test2 VALUES (2, 20, 'row2', GETDATE());
INSERT INTO two_way_test2 VALUES (3, 30, 'row3', GETDATE());
INSERT INTO two_way_test2 VALUES (4, 40, 'row4', GETDATE());
INSERT INTO two_way_test2 VALUES (5, 50, 'row5', GETDATE());
INSERT INTO two_way_test2 VALUES (6, 60, 'row6', GETDATE());
INSERT INTO two_way_test2 VALUES (7, 70, 'row7', GETDATE());
INSERT INTO two_way_test2 VALUES (8, 80, 'row8', GETDATE());
INSERT INTO two_way_test2 VALUES (9, 90, 'row9', GETDATE());
INSERT INTO two_way_test2 VALUES (10, 100, 'row10', GETDATE());
GO

-- Add the transactional publication and article in test1
USE test1;
GO

DECLARE @publication AS sysname; 
DECLARE @article1 AS sysname; 
DECLARE @article2 AS sysname; 
DECLARE @login AS sysname;
DECLARE @password AS nvarchar(512);
SET @publication = N'two_way_pub_test1';
SET @article1 = N'two_way_test1';
SET @article2 = N'two_way_test2';
SET @login = $(Login);
SET @password = $(Password);

EXEC sp_addlogreader_agent 
    @job_login = @login, 
    @job_password = @password,
    @publisher_security_mode = 1;

EXEC sp_addpublication @publication = @publication, 
    @restricted = N'false', 
    @sync_method = N'native', 
    @repl_freq = N'continuous', 
    @description = N'publ1', 
    @status = N'active', 
    @allow_push = N'true', 
    @allow_pull = N'true', 
    @allow_anonymous = N'false', 
    @enabled_for_internet = N'false', 
    @independent_agent = N'true', 
    @immediate_sync = N'false', 
    @allow_sync_tran = N'false', 
    @autogen_sync_procs = N'false', 
    @retention = 60;

EXEC sp_addarticle @publication = @publication,
    @article = @article1, 
    @source_owner = N'dbo', 
    @source_object = @article1, 
    @destination_table = @article2, 
    @type = N'logbased', 
    @creation_script = null, 
    @description = null, 
    @pre_creation_cmd = N'drop', 
    @schema_option = 0x00000000000000F1, 
    @status = 16, 
    @vertical_partition = N'false', 
    @ins_cmd = N'CALL sp_ins_two_way_test2', 
    @del_cmd = N'XCALL sp_del_two_way_test2', 
    @upd_cmd = N'XCALL sp_upd_two_way_test2', 
    @filter = null, 
    @sync_object = null;
GO

-- Add the transactional publication and article in test2
USE test2
GO

DECLARE @publication AS sysname; 
DECLARE @article1 AS sysname; 
DECLARE @article2 AS sysname; 
DECLARE @login AS sysname;
DECLARE @password AS nvarchar(512);
SET @publication = N'two_way_pub_test2';
SET @article1 = N'two_way_test1';
SET @article2 = N'two_way_test2';
SET @login = $(Login);
SET @password = $(Password);

EXEC sp_addlogreader_agent 
    @job_login = @login, 
    @job_password = @password,
    @publisher_security_mode = 1;

EXEC sp_addpublication @publication = @publication, 
    @restricted = N'false', 
    @sync_method = N'native', 
    @repl_freq = N'continuous', 
    @description = N'Pub2',
    @status = N'active', 
    @allow_push = N'true', 
    @allow_pull = N'true', 
    @allow_anonymous = N'false', 
    @enabled_for_internet = N'false', 
    @independent_agent = N'true', 
    @immediate_sync = N'false', 
    @allow_sync_tran = N'false', 
    @autogen_sync_procs = N'false', 
    @retention = 60;

EXEC sp_addarticle @publication = @publication,
    @article = @article2, 
    @source_owner = N'dbo', 
    @source_object = @article2, 
    @destination_table = @article1, 
    @type = N'logbased', 
    @creation_script = null, 
    @description = null, 
    @pre_creation_cmd = N'drop', 
    @schema_option = 0x00000000000000F1, 
    @status = 16, 
    @vertical_partition = N'false', 
    @ins_cmd = N'CALL sp_ins_two_way_test1', 
    @del_cmd = N'XCALL sp_del_two_way_test1', 
    @upd_cmd = N'XCALL sp_upd_two_way_test1', 
    @filter = null, 
    @sync_object = null;
GO

-- Add the transactional subscription in test1
USE test1
GO

DECLARE @publication AS sysname;
DECLARE @subscriber AS sysname;
DECLARE @subscription_db AS sysname;
SET @publication = N'two_way_pub_test1';
SET @subscriber = $(SubServer2);
SET @subscription_db = N'test2';

EXEC sp_addsubscription @publication = @publication, 
    @article = N'all', 
    @subscriber = @subscriber, 
    @destination_db = @subscription_db, 
    @sync_type = N'none', 
    @status = N'active', 
    @update_mode = N'read only', 
    @loopback_detection = 'true';

EXEC sp_addpushsubscription_agent 
    @publication = @publication, 
    @subscriber = @subscriber, 
    @subscriber_db = @subscription_db, 
    @job_login = $(Login), 
    @job_password = $(Password);
GO

-- Add the transactional subscription in test2
USE test2
GO

DECLARE @publication AS sysname;
DECLARE @subscriber AS sysname;
DECLARE @subscription_db AS sysname;
SET @publication = N'two_way_pub_test2';
SET @subscriber = $(SubServer1);
SET @subscription_db = N'test1';

EXEC sp_addsubscription @publication = @publication, 
    @article = N'all', 
    @subscriber = @subscriber, 
    @destination_db = @subscription_db, 
    @sync_type = N'none', 
    @status = N'active', 
    @update_mode = N'read only', 
    @loopback_detection = 'true';

EXEC sp_addpushsubscription_agent 
    @publication = @publication, 
    @subscriber = @subscriber, 
    @subscriber_db = @subscription_db, 
    @job_login = $(Login), 
    @job_password = $(Password);
GO

-- Create custom stored procedures in test1 
USE test1
GO

IF EXISTS (SELECT * FROM sysobjects WHERE name LIKE 'sp_ins_two_way_test1' and type = 'P')
    DROP proc sp_ins_two_way_test1;
IF EXISTS (SELECT * FROM sysobjects WHERE name LIKE 'sp_upd_two_way_test1' and type = 'P')
    DROP proc sp_upd_two_way_test1;
IF EXISTS (SELECT * FROM sysobjects WHERE name LIKE 'sp_del_two_way_test1' and type = 'P')
    DROP proc sp_del_two_way_test1;
GO

-- Insert procedure
CREATE proc sp_ins_two_way_test1 @pkcol int, 
    @intcol int, 
    @charcol char(100), 
    @datecol datetime
AS
    INSERT INTO two_way_test1 (pkcol, intcol, charcol, 
        datecol) 
    VALUES (@pkcol, @intcol, @charcol, GETDATE());
GO

-- Update procedure
CREATE proc sp_upd_two_way_test1 @old_pkcol int, 
    @old_intcol int, 
    @old_charcol char(100), 
    @old_datecol datetime,
    @pkcol int, @intcol int, 
    @charcol char(100), 
    @datecol datetime
AS
    -- IF intcol conflict is detected, add values
    -- IF charcol conflict detected, concatenate values
    DECLARE  @curr_intcol int, @curr_charcol char(100);

    SELECT @curr_intcol = intcol, @curr_charcol = charcol 
    FROM two_way_test1 WHERE pkcol = @pkcol;

    IF @curr_intcol != @old_intcol
        SELECT @intcol = @curr_intcol + 
            (@intcol - @old_intcol);

    IF @curr_charcol != @old_charcol
        SELECT @charcol = rtrim(@curr_charcol) + 
            '_' + rtrim(@charcol);

    UPDATE two_way_test1 SET intcol = @intcol, 
        charcol = @charcol, datecol = GETDATE()
    WHERE pkcol = @old_pkcol;
GO

-- Delete procedure
CREATE proc sp_del_two_way_test1 @old_pkcol int, 
    @old_intcol int, 
    @old_charcol char(100), 
    @old_datecol datetime
AS
    DELETE two_way_test1 WHERE pkcol = @old_pkcol;
GO

-- Create custom stored procedures in test2
USE test2
GO

IF EXISTS (SELECT * FROM sysobjects WHERE name LIKE 'sp_ins_two_way_test2' and type = 'P')
    DROP proc sp_ins_two_way_test2;
IF EXISTS (SELECT * FROM sysobjects WHERE name LIKE 'sp_upd_two_way_test2' and type = 'P')
    DROP proc sp_upd_two_way_test2;
IF EXISTS (SELECT * FROM sysobjects WHERE name LIKE 'sp_del_two_way_test2' and type = 'P')
    DROP proc sp_del_two_way_test2;
GO

-- Insert procedure
CREATE proc sp_ins_two_way_test2 @pkcol int, 
    @intcol int, 
    @charcol char(100), 
    @datecol datetime
AS
    INSERT INTO two_way_test2 (pkcol, intcol, charcol,datecol) 
        VALUES (@pkcol, @intcol, @charcol, GETDATE());
GO

-- Update procedure
CREATE proc sp_upd_two_way_test2 @old_pkcol int, 
    @old_intcol int, 
    @old_charcol char(100), 
    @old_datecol datetime,
    @pkcol int, 
    @intcol int, 
    @charcol char(100), 
    @datecol datetime
AS
    -- IF intcol conflict is detected, add values
    -- IF charcol conflict detected, concatenate values
    DECLARE  @curr_intcol int, @curr_charcol char(100);

    SELECT @curr_intcol = intcol, @curr_charcol = charcol 
    FROM two_way_test2 WHERE pkcol = @pkcol;

    IF @curr_intcol != @old_intcol
        SELECT @intcol = @curr_intcol + 
            (@intcol - @old_intcol);

    IF @curr_charcol != @old_charcol
        SELECT @charcol = rtrim(@curr_charcol) + 
        '_' + rtrim(@charcol);

    UPDATE two_way_test2 SET intcol = @intcol, 
        charcol = @charcol, datecol = GETDATE() 
    WHERE pkcol = @old_pkcol;
GO

-- Delete procedure
CREATE proc sp_del_two_way_test2 @old_pkcol int, 
    @old_intcol int, 
    @old_charcol char(100), 
    @old_datecol datetime
AS
    DELETE two_way_test2 WHERE pkcol = @old_pkcol;

GO

-- Execute updates to the first row in test1 and test2
USE test1
GO
UPDATE two_way_test1 SET intcol = 20 , charcol = 'updated at test1' WHERE pkcol = 1;

USE test2
GO
UPDATE two_way_test2 SET intcol = 60 , charcol = 'updated at test2' WHERE pkcol = 1;

-- Select data from both tables to verify that the changes were propagated
SELECT * FROM test1..two_way_test1 WHERE pkcol = 1;
SELECT * FROM test2..two_way_test2 WHERE pkcol = 1;
GO

See Also

Concepts

Replication System Stored Procedures Concepts

Specifying How Changes Are Propagated for Transactional Articles

Bidirectional Transactional Replication