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Data Warehousing
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In an increasingly computerized
business environment, it has become much easier for
organizations to collect and store large amounts of
information. Government agencies in particular have
amassed great volumes of data on their clients and programs.
Decision-makers are often interested in finding more
expedient, more meaningful ways to save and analyze
these large collections of data. A technology called
data warehousing answers precisely this need. Data warehouses
can organize vast amounts of data from different sources,
helping analysts answer timely questions and identify
relevant patterns. These discoveries can be the key
to better decisions and wise use of scarce resources.
What are Data Warehouses?
The amount of data
available in a large, complex organization may be overwhelming.
Some decision-makers may not even be fully aware of
all the data that are actually collected. Furthermore,
data are often collected on the same population by multiple
agencies but stored in different locations. Data warehouses
are one way to make data more manageable and more accessible
for the researchers and decision-makers that need it
most.
Data warehouses serve as a central repository for all
or most of the data collected by the various operating
units and systems of an organization. A data warehouse
organizes and stores data with a long historical perspective.
The data are presented on a common platform from which
information processing and analysis can take place.
Data can then be analyzed from the perspective of the
organization as a whole, rather than by individual units
of organizations. The analysis can take the form of
queries constructed to answer a specific question, but
it may also take the form of sophisticated data mining.
Data mining, as the name implies, examines the data
as a whole in an effort to identify ("mine")
key trends or associations that may otherwise have been
overlooked.
To harness the true power of
a data warehouse, it is important to recognize how it
differs from traditional databases. As an analytical
tool, the design of a data warehouse generally starts
not with a review of specific user requirements, but
with an analysis of the data itself. Planners need to
first consider what data sources already exist and how
the information they contain can best be centrally collected.
If planned on a solid foundation, a data warehouse can
begin on a small scale and continue to grow to meet
the changing needs of the organization it serves. Related
to data warehousing is the concept of the data mart.
It, too, is a repository of data gathered from various
sources, but it is created specifically to serve a particular
group of users in an organization. The content, interface,
and functions of a data mart reflect the unique needs
of a segment of an organization, whereas a data warehouse
is less specialized. For example, a corporation may
have a data warehouse that every department can access,
but the sales department may have its own data mart.
Together, data warehouses and data marts can work to
transform data from a latent resource into a powerful,
dynamic information tool.
Data Warehousing: A State
Case
Texas is one of a
growing number of States implementing data warehouses
to facilitate child welfare practice. The CAPS (Texas
SACWIS) data warehouse is still a work in progress,
but has already been well received.
The idea to use data warehousing started when Texas
officials encountered difficulties generating ad hoc
management reports from their new SACWIS system. The
new system was proving too complex for users to generate
ad hoc reports. The new system contains about three
hundred tables and data elements that changed from what
existed in the legacy system. Most users were not skilled
enough to make effective use of the ad hoc reporting
tool that Texas had chosen during the planning and development
process. Indeed, even expert users were challenged by
the task of creating queries based on the new data elements
and complex table structures in the new system.
CAPS staff came up with the concept of a warehouse to
facilitate reporting. The CAPS data warehouse is an
Oracle 8 database. The reports are generated using the
Oracle Reports software contained in the Oracle Enterprise
Developer's Suite. It is made up of a number of data
marts; each focused on a specific facet of the child
welfare process. Currently, modules for Intake, Investigations,
Permanency Planning, Substitute Care, Family Stages
which includes Substitute Care and Family Reunification,
and Adult Protective Services Service Delivery have
been completed with several more in development.
The data marts are designed
in a star configuration, which places key data in a
central table or set of tables and places additional
details in secondary, linked locations. The single,
biggest task in designing the data marts has been getting
user buy in. The first step was to identify the stakeholders
such as staff reporting to the legislature, regional
and program managers, and supervisors. Users were first
queried as to what types of questions they would like
answered. They were then asked to agree on definitions
for the data that would make up the answers to those
questions (e.g., what constitutes an intake?). Once
those questions were answered, CAPS staff could begin
designing the data mart. The final big issue was the
decision on how often the data would be updated. The
decision was made to populate the data warehouse on
a monthly basis, with updates at three months on a rolling
basis with a 12 month fiscal year ending update to coincide
with the timetable of annual reports to the legislature.
CAPS staff is not resting on their accomplishment with
the data warehouse. They have implemented a web-enabled
front end that allows users to access the 300 or so
canned reports and ad hoc capability of the system via
the State Intranet. Such an interface would place the
power of the warehouse at user's fingertips in an easy
to understand, user-friendly format.
The CAPS data warehouse effort is being headed by CAPS
Project Manager Donna Marler and CAPS Data Administrator
Christie Mitschke. For additional information on the
CAPS data warehouse project contact Donna Marler at
(512) 834-3758.
This document was prepared as a
supplement to the material presented in add-on sessions
at the May 2000 ACF Users Group Meeting in Louisville,
KY. It is the result of collaboration between the Office
of State Systems and the National Resource Center for
Child Welfare Data and Technology. The purpose
of this document is to provide a brief overview of an
issue relevant to the development or implementation
of SACWIS systems and to the delivery of child welfare
services. It is written with the goal of being accessible
and informative to a wide audience including program
and systems staff with varying levels of comfort with
technology and policy. We hope that it will serve to
stimulate an exchange of ideas and information among
States and between systems and program staff. Your feedback
is important to us. If you have any additional information
on the topic presented in this sheet, or if you have
any comments or suggestions regarding its presentation
or content, please contact Tom Wetterhan of Xtria at
(703) 821-3090 x250 or
tomw@xtria.com.

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