Streams is well-equipped to perform such
data synchronization. For example, Streams has built-in
flexibility that allows the design of apply handlers and
on-the-fly data transformation methodologies. When multiple
sites participate in the data transfers, the goal should be to
have the data from other sites as soon as new data available.
Streams can move the data and synchronize it at multiple sites.
Data residing in database systems or data
being changed in the database systems has to be propagated to
database systems situated in other geographic locations. Data
Movement includes a variety of ways in which data is transferred
to different databases. To refresh or synchronize the data, it
can be extracted and transferred to the desired location,
overriding previously loaded data.
A simple method may involve extracting the
necessary data into text files and moving such files by the FTP
process to the desired host machine to load into the relational
database. In another method, third party tools such Informatica
or other data handling tools, which connect to multiple database
systems concurrently, can move data by using the
extract-transfer mechanism. Products such as DBArtisan can do
transfers from one database to another, on demand, by managing
internally using a bulk transfer mechanism.
For instance, production database system
data is often moved into a development or QA database system.
This may be done on a scheduled basis or can be done on-demand.
In another example, data at the end of business hours may be
sent to external agencies or to internal data warehousing
systems to be used for refreshing the summaries.