According to my system i have maintained two databases in LAN and online db.But i want to synchronize these two databases. I hope to do this things using microsoft sync frame work.
.http://msdn.microsoft.com/en-us/library/ee819079.aspx
Can i do sync local and online sql db using this? or any suitable method for do this.thank you
Sync Framework is designed for occasionally connected systems, eg. a laptop that can access the corporate network every other day and update its database, but needs to work when it has no corpnet access too. The pairing of Sync Framework is usually a central DB (SQL Server) and local embedded SQL Server Compact or SQL Express on the devices (laptops, phones, tablets etc).
IF the databases are always connected (eg. two DBs in two servers, with 24x7 connectivity between them, even if over Internet) then the appropriate technology is replication. Either Merge or Transactional. Theoretically replication also works when disconnect periods are expected, but Sync Framework is much better at it, and most importantly Sync Framework is not strongly dependent on DNS names as replication is (very important for occasionally connected systems).
Synchronizing the database is a vague term, you have to consider if you want a Master-Slave replication shcme or a Master-Master (the later being very difficult to achieve) and you have to consider what do you want replicated from the database. You also need to consider if more partners will be later added (more databases to 'synchronize'). And you have to be way more careful now about schema changes.
Related
can someone give me a clear idea about which technique/ method is more reliable, less memory consuming and faster in replicating data from one Database to another in MSSQL database(SQl Server 2012) and why. We are in the process of developing a Live GPS based tracking application and I am confused with which method to proceed with
Trigger Based Replication (Live Sync)
(OR)
Transactional Replication
Thanks in Advance ☺
I would recommend using standardised solutions whenever possible. Within the choice given to you, transaction replication should be an obvious favourite, because:
It doesn't require any coding and can be deployed using standard tools. This makes it much faster to deploy and maintain - any proper DBA can do it, some of them even being blindfolded.
Actual data transfer is done by replication agents which are separate applications external to the SQL Server process and client connections. Any network issues within the publisher-distributor-subscriber(s) chain will lead to delays in copying the data, but they will not affect the performance of the publisher database itself.
With triggers, you have neither of these advantages: you will have to add a lot of code, and sluggish network will make data-changing queries slower, potentially leading to timeouts.
Of course, there are many more ways to move the data between the databases in SQL Server, such as (in no particular order):
AlwaysOn Availability Groups (Database mirroring);
Log shipping;
CDC (Change Data Capture);
Service Broker.
However, given your needs, transaction replication still looks like your best bet, overall.
We are currently migrating our whole IT systems (application server, web server, DBMS etc.) to a new datacenter. The systems used before have been spread out across several datacenters in Europe and one of the goals for this migration was to have it all in one place, in one private cloud. After an initial migration of the productive systems on a particular day, we are right now reconfiguring the whole systems, going to be testing them thoroughly. Afterwards we will have to bring the newly migrated, configured and tested systems to the latest version and will use the new system.
The systems so far have been using several large SQL Server 2008 databases, transferring them to the new datacenter has been quite painful, and had to be done via harddrive, since the outgoing network connection from that old location is only 10 Mbit. So I don't want to use a brute force approach to redo the whole way through using a harddrive, so transport the whole databases, I'd rather like to use database tools to get the job done.
I've heard of several technologies applicable for this, varying from SQL Server Replication to the Sync Framework, but I would like to know which of them would be the best for a one time synchronization of such larger databases, having especially in mind the rather slow outgoing network connection and a forced disconnect every 24 hours at that old Location.
I'd still go for Sync Framework, but the more I read about it, it seems to be rather targeted for scenarios where you want to implement periodic updates between several databases, so I'm unsure if I overlooked a rather simple and easier solution for this synchronization.
I read in a few places that SQL Azure data is automatically replicated and the Azure platform provides redundant copies of the data, Therefore SQL Server high availability features such as database mirroring and failover cluster aren't needed.
Has anyone got a chance to investigate deeper into this? Are all those availability enhancements really not needed in Azure? Thanks!
To clarify, I'm talking about SQL as a service and not a VM hosted SQL.
The SQL Database service (database-as-a-service) is a multi-tenant database service, and your databases are triple-replicated within the data center, providing durable storage. The service itself, being large-scale, provides high availability (since there are many VMs running the service itself, along with replicated data). Nothing is needed in terms of mirroring or failover clusters. Having said that: If, say, your particular database became unavailable for a period of time, you'll need to consider how you'll handle that situation (perhaps sync'ing to another SQL Database, maybe even in another data center).
If you go with SQL Database (DBaaS), you'll still need to work out your backup strategy, and possibly syncing with another DC (or on-premises database server) for DR purposes.
More info on SQL Database fault tolerance is here.
Your desired detail is probably contained in this MSDN article of Business Continuity and Azure SQL Database (see: http://msdn.microsoft.com/en-us/library/windowsazure/hh852669.aspx). At the most basic level Azure SQL Database will keep three replicas of your database - one primary and two secondary.
While this helps with BCP / DR scenarios you may also wish to investigate ways to backup your database so you have point-in-time restore capabilities. More information on backup / restore can be found here: http://msdn.microsoft.com/en-us/library/windowsazure/jj650016.aspx
We have a hr system that holds employee data and have many remote databases that use this data. Currently we use a mixture of copying the data across periodically to the remote databases and pulling the data across using views at runtime. Im curious as to which option you think is best. My personal preference is to copy the data across periodically as it removes the dependency from the master databases. However it seems both have pros and cons
Whats the best practice for this?
Thanks
p.s we have a mixture of sql2000, 2005 and s008 servers
Part of the answer will depend on what level of latency is acceptable for the other systems that use the HR data. Is a day behind OK? an Hour? or does it need to be current?
Each instance could result in a different solution.
I prefer a data pull instead of a push. The remote decides when it needs its data and you can encapsulate all that logic on the server where it belongs. In a push, you have to keep processes on the HR server in synch with the demands of the subsystem.
I have reservations about multiple remote databases querying a source system directly. If some latency is not an issue, build a process on the HR system to snapshot the required data into some local tables (or a data warehouse?) and have all remotes query this data. At the very least, build local views against the HR source and only allow remote servers rights to those.
Are you doing this across a linked server? If so, I recommend creating synonyms on the remote that point to the HR source across the link. This will allow you to move source data locations around and only have to change your synonym definition.
Im looking at developing a simple ecommerce platform and need to replicate product and customer data to the web host over the internet so the website can run disconnected. The two options i can think of at present are using enterprise messaging and database replication.
Im leaning towards database replication over enterprise messaging as enterprise messaging would require additional developer resource to write all the plumbing code. Anyone have any success using sql server one way replication over unreliable wan links through the internet?
I'm sorry I missed this... NitroAccelerator from Nitrosphere.com is built exactly to speed up replication over the internet. It compresses the TDS packets very efficiently and results in 80-90% improvement in replication times.
In the last company I worked for we had full merge replication for some of our customers.
There were 2 scenarios
Merge Replication for hanadheld devices
Some of our customers had PDAs and they subscribed to some published tables of our main database. They were disconnected for large periods and merge replication worked fine and updated changes on both sides when the connection was restored
Full site to site Merge Replications
This was used for customers that had remote offices but required a fully synchronized local database for performance reasons. In most cases the VPN was extremely poor and we did have some instances of the VPN being down for a week and on restoration replication synchronized both database without an issue.
In both cases replication seems to be very fault tolerant and performed very well.
In your case its one way replication so there should not be no merge conflicts to deal with making the situation easier.
There is a learning curve with replication but as a technology it works very well I found even over poor connections.
Liam