Words to live by
- By Alan R. Earls
- August 1, 2005
According to Forrester Research analyst Phil Russom, there are several competing
terms that are either equivalent to on-demand data warehousing, or are closely
Teradata, for example, talks about active data warehousing, while other vendors
talk about real-time data warehousing. However, Russom stresses, real
time should be distinguished as more of a push technology, while on-demand is
more of a pull technology. “On-demand (generally associated with
IBM) is often, by its nature, more attuned to the real needs of the business
rather than to simply what IT is able to accomplish with more technology,”
By contrast, real time “hurls data at users whether they need
or want it,” Russom says. Although on-demand can sometimes deliver
results in real time, in some cases queries can still take minutes or even an
hour or two to yield results. “But that’s still much better than
overnight,” Russom adds.
“The real-time data warehouse is optimized for bulk loading of many gigabytes
of data,” Russom says. By contrast, on-demand typically focuses
on small pieces of information as they are created or changed.
Then there is an operational data store which an enterprise often needs in
front of a data warehouse if it is to achieve real time. Many operational data
stores are home grown, Russom says.
Enterprise information integration is another term that often gets
lumped with on-demand data warehouse. Russom says IBM’s WebSphere
Information Integrator is a leading example of that.
EII is sometimes used as a replacement for real time because it can go and
get the data when it’s needed. “It’s not a replacement for
a data warehouse, it is a supplement,” Russom says. But EII has limitations.
“It can’t handle large volumes of data, Russom notes, and if
you want to do true data analysis as
opposed to mere access, EII can’t help much.”
Mark Beyer from Gartner also offers some entries for the lexicon. For instance,
he notes, ad hoc, reporting and OLAP often get mentioned in conjunction with
on-demand. Ad hoc, he says, means an undefined use for data. OLAP means “I
have a defined use but don’t know where the analysis will go, and reporting
means I do have a defined use.”
Back to Feature: Real
Time is the Right Time
Alan R. Earls is a technology and business writer based near Boston.