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What is Replication Server in Sybase?

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What is Replication Server in Sybase?

Replication Server moves transactions (insert, updates and deletes) at the table level from a source dataserver to one or more destination dataservers. The dataserver could be ASE or other major DBMS flavour (including DB2, Informix, Oracle). The source and destinations need not be of the same type.

What can it do ?
* Move data from one source to another.
* Move only a subset of data from source to destination. So, you can ‘subscribe’ to a subset of data, or a subset of the columns, in the source table, e.g. select * from clients where state = ‘NY’
* Manipulation/transformation of data when moving from source to destination. E.g. it can map data from a data-type in DB2 to an equivalent in Sybase.*
* Provide a warm-standby system. Can be incorporated with Open Switch to provide a fairly seamless fail-over environment.
* Merge data from several source databases into one destination database (could be for a warehouse type environment for example).
* Move data through a complicated network down to branch offices, say, only sending the relevant data to each branch.


(* This is one of Sybase replication's real strengths, the ability to define function string classes which allow the conversion of statements from one SQL dialect to match the dialect of the destination machine. Ed)

How soon does the data move
The data moves asynchronously. The time it takes to reach the destination depends on the size of your transaction, level of activity in that particular database (a database as in Sybase systems), the length of the chain (one or more replication servers that the transaction has to pass through to reach the destination), the thickness of pipe (network), how busy your replication server is etc. Usually, on a LAN, for small transactions, this is about a second.

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