Transactional Replication

Please help me..
After configuring Transactional Replication with  a publisher, distributor , subscriber and with one database and one table . and in subscriber the database in read write mode. so, we can perform changes .   Here my question is....
we performed some changes in table (other than primary key column) in subscriber db.  
Then both db's have different vales ( publisher db and subscriber db). how will face this scenario? 

Hi,
As Hilary said, if you make changes in the publisher database, the data which you changed on the same row in the subscriber database will be replaced.
Do you want to synchronize the changes between subscriber and publisher in both directions? If so, you need to Merge replication.
Merge replication, like transactional replication, typically starts with a snapshot of the publication database objects and data. Subsequent data changes and schema modifications made at the Publisher and Subscribers are tracked with triggers.
The Subscriber synchronizes with the Publisher when connected to the network and exchanges all rows that have changed between the Publisher and Subscriber since the last time synchronization occurred.
Thanks.
Tracy Cai
TechNet Community Support

Similar Messages

  • Invalid rowid error while running the snapshot agent in transactional replication

    Hi All,
    I am getting an Invalid rowid error while replicating an large tables i.e around 30 millions rows from oracle(publisher) to sql server(Subscriber) while running the snapshot agent in transactional replication.
    Its taking around 18 hours and its then its throwing this error.
    Is there any faster way that i can replicate the initial snapshot this large table as 18 hours is very high on time.
    Kindly suggest.i am always got quick and accurate response always..hope the same in this case also.
    Thanks,

    Hi,
    Could you please create a replication with some small tables for a test?
    You can disable the firewall on both sides and rerun snapshot. Enable verbose logging to level 4 for snapshot agent and check the results if it fails.
    http://support.microsoft.com/kb/312292
    Here is a document says for the error: ORA-10632: Invalid rowid Cause: Segment Highwatermark was overwritten due to shrink and space reused Action: Reissue this command.
    I also suggest you contact the Oracle support team for further help.
    Thanks.
    Tracy Cai
    TechNet Community Support

  • Error while setting up Transactional Replication

    Hi Team,
    I am getting below error while configuring Transactional Replication.
    Specifically, when I started configuring the distributor that when I am getting below error. I am getting this in GUI as well TSQL script as well.
    SQL Server could not configure 'TEST-PC\SQL2K8' as a Distributor.
    ADDITIONAL INFORMATION:
    An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)
    Destination path D:\SQL2K8DATA is not valid. Unable to list directory contents. Specify a valid destination path.
    Changed database context to 'master'. (Microsoft SQL Server, Error: 14430)
    Background of the error.
    ========================
    I installed 3 sql instances of "SQL Server 2008 Developer edition, SP3 (x64)".
    I started configuring a remote distributor using one of the instance and error started popping up.
    Initially I had the replication running fine and I removed it and tried to reconfigure distributor thats when the error starting popping up.
    The folder physically exists and the service account has full permissions and I have logged in as service account and trying to setup Transactional Replication.
    He is local administrator on the box and also sysadmin login at sql server level.
    Not sure why this error is popping up.....
    After wasting a lot of time. I tried to install 3 new fresh instances with same service pack level i.e. sp3, but still the error remains the same.
    Appreciate if anyone can guide me resolving this issue.
    Thank you.

    Hi Brandon,
    I generated the script and tried again. No Luck. It is throwing error at creation of distribution database itself i.e. exec sp_adddistributiondb .
    /****** Scripting replication configuration. Script Date: 2/25/2014 11:43:31 AM ******/
    /****** Please Note: For security reasons, all password parameters were scripted with either NULL or an empty string. ******/
    /****** Installing the server as a Distributor. Script Date: 2/25/2014 11:43:31 AM ******/
    use master
    go
    exec sp_adddistributor
    @distributor = N'TEST-PC\S2',
    @password = N'123'
    GO
    exec sp_adddistributiondb
    @database = N'distribution',
    @data_folder = N'C:\Program Files\Microsoft SQL Server\MSSQL10.S2\MSSQL\Data',
    @log_folder = N'C:\Program Files\Microsoft SQL Server\MSSQL10.S2\MSSQL\Data',
    @log_file_size = 2,
    @min_distretention = 0,
    @max_distretention = 72,
    @history_retention = 48,
    @security_mode = 1
    GO
    Error Message :
    Msg 14430, Level 16, State 1, Procedure sp_adddistributiondb, Line 227
    Destination path C:\Program Files\Microsoft SQL Server\MSSQL10.S2\MSSQL\Data is not valid. Unable to list directory contents. Specify a valid destination path.
    use [distribution]
    if (not exists (select * from sysobjects where name = 'UIProperties' and type = 'U '))
        create table UIProperties(id int)
    if (exists (select * from ::fn_listextendedproperty('SnapshotFolder', 'user', 'dbo', 'table', 'UIProperties', null, null)))
        EXEC sp_updateextendedproperty N'SnapshotFolder', N'\\TEST-PC\repldata', 'user', dbo, 'table', 'UIProperties'
    else
        EXEC sp_addextendedproperty N'SnapshotFolder', N'\\TEST-PC\repldata', 'user', dbo, 'table', 'UIProperties'
    GO
    exec sp_adddistpublisher @publisher = N'TEST-pc\s1',
    @distribution_db = N'distribution',
    @security_mode = 1,
    @working_directory = N'\\TEST-PC\repldata',
    @trusted = N'false',
    @thirdparty_flag = 0,
    @publisher_type = N'MSSQLSERVER'
    GO

  • Running transactional replication on SQL server 2008R2 but: "The process could not connect to subscriber 'SERVER NAME'"

    I've set up Replication (transactional replication) between two remote servers. On the one of server that I configure Distribution & publication .another server is subscription. The subscription is all set & snapshot agent is started .but the actual
    replication doesn't take place.
    When viewing the Synchronization Status of the subscription, i get an error, saying "The process could not connect to Subscriber ‘Server name'."
    Clicking on start, this is the error message I get:
    The agent could not be started.
    Additional information:
    An exception while executing a Transact-SQL statement or batch.
    SQL Server Agent Error: Request to run job Server1-EDUSRV-Pubs-Server2-14 (from User Server1\Administrator) refused because the job is already running from a request by User sa.
    Change database context to 'EDUSRV'.(Microsoft SQL Server Error:22022)
    What can i do?
    Please help me.Thanks

    The error The process could not connect to Subscriber 'Server name' indicates that the Distribution Agent process account does not have enough permissions to connect to the Subscriber.
    If this is a push subscription, verify the Distribution Agent process account is db_owner in the distribution and subscription databases, is a member of the PAL, and has read permissions on the snapshot share.
    If this is a pull subscription, verify the Distribution Agent process account is db_owner in the subscription database, is a member of the PAL, and has read permissions on the snapshot share.
    The permissions required are covered in
    Replication Agent Security Model.
    If you have anymore questions, please let me know.  I hope this helps.
    Brandon Williams (blog |
    linkedin)

  • Transactional replication from a failover cluster instance to a SQL Server Express DB

    Hello,
    I have been poking around on Google trying to understand if there are any gotchas in configuring transactional replication on a instance DB of a failover cluster, to a SQL Server Express DB. Also, this client would like to replicate a set of tables between
    two instances DB's which both reside on nodes of the cluster.
    Everything I've read suggests there is no problem using transactional replication on clustered instance as long as you use a shared snapshot folder. I still have some concerns:
    1) Should the distributor need to live on a separate instance?
    2) What happens in the event of an automatic, or manual failover of a publisher, especially if the distributor does not need to live on a separate instance? I know that when a failover occurs, all jobs in progress are stopped and this seems like a recipe for
    inconsistency between the publisher and subscriber.
    There is a paramount concern, that this particular client won't have staff on hand to troubleshoot replication if there are problems, hence my hesitancy to implement a solution that relies on it.
    Thanks in advance.

    1) Should the distributor need to live on a separate instance?
    Answer: It is recommended to configure the distributor on the different server, but it also be configured on Publisher/subscriber server. (Subscriber in our case is not possible as its a Express edition)
    2) What happens in the event of an automatic, or manual failover of a publisher, especially if the distributor does not need to live on a separate instance? I know that when a failover occurs, all jobs in progress are stopped and this seems like a recipe for
    inconsistency between the publisher and subscriber. There is a paramount concern, that this particular client won't have staff on hand to troubleshoot replication if there are problems, hence my hesitancy to implement a solution that relies on it.
    Answer: If you configure both publisher and distributor on the same server and the SQL instance is failed over, the data synchronization/replication is suspended till the instance comes online. 
    Once the instance is up,all the replication jobs will start again and it will continue to synchronize the data to subscriber. No manual intervention is required.

  • Taking snapshot of oracle tables to sql server using transactional replication is taking a long time

    Hi All,
    I am trying to replicate around 200 oracle tables onto sql server using transaction replication and it taking a long time i.e the initial snapshot is taking more than 24 hrs and it still going on.
    Is there any way to replicate those these tables faster?
    Kindly help me out..
    Thanks

    Hi,
    According to the description, I know the replication is working fine. But it is very slow. 
    1. Check the CPU usage on Oracle publisher and SQL Server. This issue may due to slow client processing (Oracle performance) or Network performance issues.
    2. Based on SQL Server 2008 Books Online ‘Performance Tuning for Oracle Publishers’ (http://msdn.microsoft.com/en-us/library/ms151179(SQL.100).aspx). You can enable the transaction
    job set and follow the instructions based on
    http://msdn.microsoft.com/en-us/library/ms147884(v=sql.100).aspx.
    2. You can enable replication agent logging to check the replication behavior. You may follow these steps to collect them:
    To enable Distribution Agent verbose logging. Please follow these steps:
    a. Open SQL Server Agent on the distribution server.
    b. Under Jobs folder, find out the Distribution Agent.
    c. Right click the job and choose Properties.
    d. Select Steps tap, it should be like this:
    e. Click Run agent and click Edit button, add following scripts by the end of scripts in the command box:
            -Output C:\Temp\OUTPUTFILE.txt -Outputverboselevel 2
    f. Exit the dialogs
     For more information about the steps, please refer to:
    http://support.microsoft.com/kb/312292
    Hope the information helps.
    Tracy Cai
    TechNet Community Support

  • Transactional Replication Stalled.

    Hi,
    We are having a Transactional  replication issue where the Data does not get replicated  and the log Just keeps grawing.
    Last week we had an accidental load 15 Million records, on one of  the T replication enabled   Db's .Then  the replication stopped working i mean i look at the replication monitor it says NO transactions to replicate but we have a lot difference
    with the DATA.I  also see that the logfile file for the DB is growing.  
    1.I did a few things like stopping the log reader and restarting.
    2.Reinitialize the Snapshot ,the snapshot is taken but is not being applied  to the subscriber .No error msg that i can see.
    So had to drop the replication entirely , shrink the log  and recreate it adding few bunches of articles, creating a snapshot for them wait until they are applied and then add the other articles which worked fine for few days , and  DB replication
    stopped again and log started growing.This time it is also effecting other replications this time too.
    I am running out of options can some one plz help!
    THanks,
    Jack

    That message means the log reader agent is going through the log reading commands from it. If your ETL operation does large batch operations replication many not be able to keep up. You might need to break these batches up into smaller batches - batchsize
    works well here.
    Another thing to consider is to do your ETL operation on both sides. This works well if the only source of changes occurs from the ETL process - then you would not publish these tables.
    If not - think about use MaxCmdsInTran - you can set this to something like 10,000 which means that if you do a million row update - the log reader agent will start to read the commands out of the log for every 10,000 changes and replicate them to the subscriber
    - before the transaction is committed on the publisher.
    This is a command that you can put in your log reader agent profile so you can turn it off when the ETL process is done and replicated.
    looking for a book on SQL Server 2008 Administration?
    http://www.amazon.com/Microsoft-Server-2008-Management-Administration/dp/067233044X looking for a book on SQL Server 2008 Full-Text Search?
    http://www.amazon.com/Pro-Full-Text-Search-Server-2008/dp/1430215941

  • Transactional replication very slow with indexes on Subscriber table

    I have setup Transactional Replication for one of our databases where one table with about 5mln records is replicated to a Subsriber database. With every replication about 500-600.000 changed records are send to the Subscriber.
    Since one month I see very strange behaviour when I add about 10 indexes to the Subscriber table. As soon as I have added the indexes replication speed becomes extremely slow (almost 3 hours for 600k records). As soon as I remove the indexes the replication
    is again very fast, about 3 minutes for the same amount of records.
    I've searched a lot on the internet to solve this issue but can't find any explaination for this strange behaviour after adding the indexes. As far as I know it doesn't have to be a problem to add indexes to a Subscriber table, and it hasn't been before on
    another replication configuration we use.
    Some information from the Replication Log:
    With indexes on the Subscriber table
    Total Run Time (ms) : 9589938 Total Work Time : 9586782
    Total Num Trans : 3 Num Trans/Sec : 0.00
    Total Num Cmds : 616245 Num Cmds/Sec : 64.28
    Total Idle Time : 0 
    Writer Thread Stats
    Total Number of Retries : 0 
    Time Spent on Exec : 9580752 
    Time Spent on Commits (ms): 2687 Commits/Sec : 0.00
    Time to Apply Cmds (ms) : 9586782 Cmds/Sec : 64.28
    Time Cmd Queue Empty (ms) : 5499 Empty Q Waits > 10ms: 172
    Total Time Request Blk(ms): 5499 
    P2P Work Time (ms) : 0 P2P Cmds Skipped : 0
    Reader Thread Stats
    Calls to Retrieve Cmds : 2 
    Time to Retrieve Cmds (ms): 10378 Cmds/Sec : 59379.94
    Time Cmd Queue Full (ms) : 9577919 Full Q Waits > 10ms : 6072
    Without indexes on the Subscriber table
    Total Run Time (ms) : 89282 Total Work Time : 88891
    Total Num Trans : 3 Num Trans/Sec : 0.03
    Total Num Cmds : 437324 Num Cmds/Sec : 4919.78
    Total Idle Time : 0 
    Writer Thread Stats
    Total Number of Retries : 0 
    Time Spent on Exec : 86298 
    Time Spent on Commits (ms): 282 Commits/Sec : 0.03
    Time to Apply Cmds (ms) : 88891 Cmds/Sec : 4919.78
    Time Cmd Queue Empty (ms) : 1827 Empty Q Waits > 10ms: 113
    Total Time Request Blk(ms): 1827 
    P2P Work Time (ms) : 0 P2P Cmds Skipped : 0
    Reader Thread Stats
    Calls to Retrieve Cmds : 2 
    Time to Retrieve Cmds (ms): 2812 Cmds/Sec : 155520.63
    Time Cmd Queue Full (ms) : 86032 Full Q Waits > 10ms : 4026
    Can someone please help me with this issue? Any ideas? 
    Pim 

    Hi Megens:
    Insert statement might be slow with not only indexes and few others things too
    0) SQL DB Blocking during inserts
    1) If any insert triggers are existed
    2) Constraints - if any
    3) Index fragmentation
    4) Page splits / fill factor
    Without indexes inserts will be fast because, each time when new row going to insert to the table, SQL Server will do
    1) it will check for the room, if no room page splits will happen and record will placed at right place
    2) Once the record updated all the index should be update
    3) all these extra update work will cause can make insert statement bit slow
    Its better to have index maintenance jobs frequently to avoid fragmentation.
    If every thing is clear on SQL Server Side, you need look up on DISK IO, N/W Latency between the servers and so on
    Thanks,
    Thanks, Satish Kumar. Please mark as this post as answered if my anser helps you to resolves your issue :)

  • Transactional Replication: Alter view changes are not reflect on Subscription database

    Hi All,
    we are configured transactional replication in our environment on sql server 2008 R2 , Yesterday I made a view alter on publisher database the view also present in replicated articles but unfortunately the changes not reflect in subscription, I already have
    checked the : Replicate Schema change option in Subscription option its also true, there is not latency exist in replication monitor , i have checked the blocking on subscription and publication. one more thing I tested the changes on replicated table its
    working fine
    Please help me to fix the issue.
    Regards,
    Pawan Singh
    Thanks

    Hi Pawan,
    According to your description, the alter on the view in publication doesn't be reflected in subscription database. As my analysis, the issue could be caused by that the distribution agent job doesn’t run after altering the view.
    I make a test on my computer, and set up transactional replication to replicate tables and views. Firstly, when creating subscription, I set the distribution agent job ‘Run continuously’(as the screenshot below), and alter the view in publication database,
    then the change is successfully reflected to the corresponding view in subscription database.
    However, I also make another test with setting the distribution agent job ‘Run on demand only’(It is determined by you), and find that it is not reflected to subscription database unless I run the distribute agent job manually.
    The distribution agent is used to read the updated transactions written to the distribution database and applies the change to the subscription database, so please check if your distribution agent job runs after you alter the view. If not, please run the
    job and check if the issue still occurs.
    Regards,
    Michelle Li

  • In SQL Server Transactional replication what all changes I can do on subscriber table

    In SQL Server Transactional replication what changes I can do on subscriber table
    Thanks

    Hi Ajay.G,
    According to your description, if you want to do some updates at the Subscriber, you need to note the following things.
    •If TIMESTAMP or IDENTITY columns are used, and they are replicated as their base data types, values in these columns should not be updated at the Subscriber.
    •Subscribers cannot update or insert text, ntext or image values . Instead, you could partition the text and image columns into a separate table and modify the two tables within a transaction.To update large objects at a Subscriber, use the
    data types varchar(max), nvarchar(max), varbinary(max) instead of text, ntext, and image data types, respectively.
    •Updates to unique keys (including primary keys) that generate duplicates and then they are not allowed and will be rejected because of a uniqueness violation.
    •If the Subscriber database is partitioned horizontally and there are rows in the partition that exist at the Subscriber but not at the Publisher, the Subscriber cannot update the pre-existing rows.
    For more information, see: Updatable Subscriptions for Transactional Replication
    Regards,
    Sofiya Li
    Sofiya Li
    TechNet Community Support

  • How to verify replication is in sync or not in transactional replication

    Hi Freinds,
    How o verify whether transactional replication is in sync.
    Thanks in advancce.
    Shashikala

    They are many ways,
    Monitoring Replication with Replication Monitor
    http://msdn.microsoft.com/en-us/library/ms151780%28v=sql.105%29.aspx
    Through Programing:
    http://msdn.microsoft.com/en-us/library/ms147874%28v=sql.105%29.aspx
    By row counts
    http://www.sqlservercentral.com/articles/Replication/70545/
    By using Validate option
    http://sqlblog.com/blogs/maria_zakourdaev/archive/2012/03/06/transactional-replication-are-you-sure-your-data-is-totally-synchronized.aspx
    Thanks,
    Thanks, Satish Kumar. Please mark as this post as answered if my anser helps you to resolves your issue :)

  • Transactional replication issue

    Hi,
    i have configured transactional replication with separate distributor server, the data copied and snapshot delivered,last 2days it is running, publisher to distributor is good, but distributor to subscriber it show heavy latency and it is showing critical
    status,when i see in the replication monitor, it shows undistributed commands 65000 records, when i see in snchronization status it showing 'deliverimg replication', when i compare to publisher and subscriber records difference is there, i checked the file
    tranfer speed 100mbps and bandwidth speed is als good....how to fix it

    Was there any issue which caused replication to stop for some time or was there any huge updates that happened at publisher..
    Take a look at this link..
    http://blogs.msdn.com/b/chrissk/archive/2009/05/25/transactional-replication-conversations.aspx
    It explains very clearly to troubleshoot this.. You might only have to look at the distribution agent latency part, as per your description...
    Apart from this, check if there are any triggers in the subscriber end which is making the subscriber updates slow..
    Regards, Ashwin Menon My Blog - http:\\sqllearnings.com

  • Transactional replication with 1 publisher 2 subscribers in SQL 2012 SE

    I have a setup of transaction replication between one publisher and subscriber in the Same server.Now, I need to add a new subscriber to the existing publisher. So publisher database name is DB_A and Subscriber 1 name is DB_B. So the new subscriber will
    be DB_C. 
    Is this kind of setup possible on one server?
    If yes then at the time of reinitialization is it going to apply the snapshot on DB_B as well as DB_C?
    Also let say if due to disk error DB_B gets corrupted then will data be still replicated between DB_A and DB_C? (Assuming publisher, subscriber 1 and 2 are sitting on individual disks)
    Need your valuable thoughts experts.
    Thanks a ton.

    For that you have to setup replication with backups. Assuming you had a failure and the only option now is to reinitialize, then instead you basically drop the subscription, change the publication property to
    allow_initialize_from_backup to true. Now you can follow the article below to create the subscription. Instead of using the backup from publisher you can use the old backup of subscriber. In this case, you need to confirm that
    all the data that is in the publisher (which needs to be replicated) is already there in subscriber.
    http://msdn.microsoft.com/en-us/library/ms147834.aspx
    Regards, Ashwin Menon My Blog - http:\\sqllearnings.com

  • Transactional Replication - Slow running sp_MSget_repl_commands

    We are running transaction replication, with a publisher and a single subscriber located in different data centres. The distribution database is located with the subsciber.
    We get high replication latency regularly, and during those times I have identified the bottleneck as the execution of sp_MSget_repl_commands by the distribution reader. Monitoring this thread in the DMV dm_exec_requests, it is consistently getting long waits
    for wait_type ASYNC_NETWORK_IO.
    Why would distribution reader by waiting on network? The thread and distribution database are all located on the same server. Is there something else that the distribution reader thread does that requires accessing the publisher?

    Do you have a remote distributor?
    Expect the ASYNC_NETWORK_IO wait type when the distribution agent is replicating over a wan/lan. Pull subscriptions may work better.
    However, you need to determine what your latency is. If your replication latency is high, server minutes, or something which does not work for you - you have a problem. Otherwise it is just an inherent limit you can't do much about.
    looking for a book on SQL Server 2008 Administration?
    http://www.amazon.com/Microsoft-Server-2008-Management-Administration/dp/067233044X looking for a book on SQL Server 2008 Full-Text Search?
    http://www.amazon.com/Pro-Full-Text-Search-Server-2008/dp/1430215941

  • Transactional Replication To 2014

    Hi All,
    In our environment we are planning to move the subscriber and distributor to 2014 with publisher on 2008. So am doing some work around on this,
    Since
    Publisher can be assigned to only a single Distributor instance, can i perform the new setting only through downtime as already a replication is running?
    Can I perform this replication without disturbing the current setup.?
    Do I need to look into any scenario/conditions except load balancing before setting up this replication? 
    Thanks
    Moug
    Best Regards Moug

    Thanks for the link. Yes the current setup is in 2008, am planning to move only distributor and subscriber. I read the article which you suggested, as per the I need to upgrade the Sql to 2014 in the current server whereas my requirement is to different
    new server. So do i need to stop all the jobs in old server and setup a replication to new server or i can perform while replication is online.? 
    Thanks.
    Best Regards Moug
    Hi Moug,
    According to your description, you had configured transactional replication on Servers, and now you want to upgrade distributor and subscribers.
     As other post, before upgrading distributor and subscribers, usually, we need to make sure that all committed transactions have been completely processed by the Log reader agent, in addition, generate scripts for the entire replication topology
    and store them in a safe place. These scripts will help to recreate replication if needed or the upgrade breaks replication.
    After performing the SQL Server 2014 upgrade on the Server, although you can restore the a backup of a replicated database from an earlier version to a server and make sure that database have the same names as the original server and preserved
    replication setting, it is rarely used as an upgrade process.  Personally, after you upgrading distributor and subscribers on the servers,
     I recommend you recreating the database and replication configuration from the above scripts, then restart SQL Server Agent and the Log Reader Agent.
    Regards,
    Sofiya Li
    Sofiya Li
    TechNet Community Support

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