DisCopy


Friday 10 August 2012

Sybase Replication Server 15 Overview

Sybase Replication Server 15 Overview
Sybase Replication Server is database replication software that moves and synchronizes data across the Servers either From Sybase ASE to ASE or to/from Other RDBMS Servers. The data moves asynchronously. The time it takes to reach the destination or to replicate data depends on the size of the transaction, level of activity in that particular database/schema, the network performance, and last but not the least how your replication server is loaded etc., Usually, on a LAN, for small transactions, this is less than a second.

Replication Server 15.0 supports a number of new ASE 15.0 features:
ü Computed columns
ü Encrypted columns
ü Partitioned tables
ü New datatypes
ü Long identifiers

1)      Computed columns
Computed columns are columns that are defined by an expression, instead of a datatype
For example
create table sales
(order_num char(20), order_date date
order_day_of_week compute datename(dw, order_date))
ü  Replication Server can only replicate materialized computed columns.
·         A materialized computed column is stored in the table
·         Virtual computed columns are not replicated

2)      Encrypted columns
ü  ASE 15.0.1, 12.5.3a, and 12.5.4 support the definition of encrypted columns
For example:
create table cust_table
(cust_id char(15),
credit_card char(20) encrypt)
Replication Server 15.0 can replicate these encrypted columns.

3)      Partitioned tables
ü  ASE 15.0 introduced semantic data partitioning
·         Tables can be partitioned by lists or ranges of key values, or by a hashing algorithm
·         These partitioning methods are supported by Replication Server 15.0
·         In addition, truncate table has been extended to support partition-level truncation

4)      New datatypes
ü  Release 15.0 adds support for new datatypes:
·         Bigint – whole numbers between -263  and 263 –1
·         Unitext – variable-width, nullable Unicode datatype

5)      Long identifiers
ü  The limit of 30 bytes for selected database and replication object names (identifiers) is extended to 255 bytes for Replication Server version 15.0. Longer identifiers are supported for these objects:
·         Tables and columns
·         Stored procedures and parameters
·         Function strings
·         Replication definitions – including table replication definitions, function replication definitions, and database replication definitions
·         Publications and articles