#database replication sql server

Check the full article and see how database replication is more than “just a copy”, it’s an enabler of distributed architecture & future-proof performance. 

# Transactional Replication – Here, data is copied from the publisher to the subscriber(s) once and subsequently transactions are delivered to the subscriber(s) as when transactions take place on the publisher. The initial copy of the data is transported as in snapshot replication in the SQL server.  # Merge Replication – This SQL server data replication tool combines data from multiple sources into a centralized database. Unlike transactional replication, this tool allows modification of the same data on publishers and subscribers, even though subscribers may be offline and not connected to the network. These are some of the important tools of SQL server data replication

Types of SQL Server Replication Tools There are three distinct types of SQL server replication tools. # Snapshot Replication This tool simply takes a “snapshot” of the data on one server and moves it to another or another database in the same server. After the first synchronization snapshot, it is possible to periodically refresh data in published tables as per the pre-programmed schedule. This is the easiest of all replication tools but comes with a rider - all data has to be copied each time a table is refreshed. Between scheduled refreshes in snapshot replication, the data on the publisher might be different from the data on the subscriber.   # Transactional Replication In transactional replication, data is copied from the publisher to the subscriber(s) once and then transactions are delivered to the subscriber(s) as and when they take place on the publisher. The initial copy of the data is transported in a similar process as snapshot replication where the SQL server takes a snapshot of data on the publisher and then forwards it to the subscriber(s). But here, as and when database users update, insert or delete records on the publisher, transactions are forwarded to the subscriber(s). # Merge Replication In this technique, data from multiple sources are combined into a single central database. As in transactional replication, merge replication also uses initial synchronization through the snapshot of data on the publisher and moves it to subscribers. But unlike transactional replication, this method permits modifications of the same data on publishers and subscribers, even though subscribers might not be connected to the network. Whenever subscribers connect to the network, merge replication tool will notice it and combine changes from all subscribers and change the existing data on the publisher. Of all SQL server replication tools, merger replication is very useful if there is a need to modify data on remote computers even in the absence of continuous connection to the network. There are some of the important concepts of SQL server replication tools.