An
ETL Tool vs. a Home Grown Solution
[Huge archives of historical data, growing volumes of
transactional data, informative external data when harvested
into business Intelligence systems and data warehouses for
decision making activities provide a competitive edge to
business houses. Yet data warehousing is an expensive
proposition and often organizations hope to reduce costs by
economizing on specific stages of the process. There is always
a raging debate on the economics of creating in-house software
versus buying off-the-shelf expensive tools. Each critical
process is evaluated in this context and the use of ETL tools
and software does not escape from this eternal debate. However,
off-the-shelf products have their own advantages and though the
programming is generic they are flexible enough for
customizations. Now there is even a new breed of off-the-shelf
ETL tools priced for the small and mid size market such as
VisualETL.]
The off-the-shelf advocates insist that business
intelligence solutions have enough challenges without having to
worry about possible lacunae in the home grown software that
may corrupt target systems and make data inconsistent. Software
like VisualETL should be used as they have proven track records
of success and have taken care of most of the data issues by a
long drawn process of experimentation and implementation.
The home grown solution advocates, on the other
hand, dismiss the off the shelf solutions on the ground that
they cannot really cater to the specific needs of a business
entity. They point out that high costs and generic programming
do not really address the specific needs of the business
entities. Home grown solutions have distinct advantages. The
low cost; the customization of the code; optimization of the
program to suit the needs; the pace at which the solution can
be built and the large knowledgebase of the programmers all
make the possibility of a home grown solution attractive. On
the other hand, it must be acknowledged that the disadvantages
out weigh the advantages. Home grown solutions are difficult to
manage and maintain. Any change to the data warehouse would
impact on the ETL solution. There would be no centralized
repository of code and the metadata capabilities would be
limited. The development cycle is large and debugging is more
difficult. Audit trials are limited or non existent. Moreover,
a small mistake in the process of Extraction, transformation
and load or a lack of foresight in the creation of the program
would result in a crippling impact on the data analysis and
interpretation. Fractures in the integration of the various
data sources would corrupt the target system and cause
incorrect representation of facts.
Off-the-shelf ETL solutions like VisualETL
provide an attractive user interface and have a centralized
storage for programs. Version control of programs is possible
and customizations of transforms become fairly simple. Metadata
support is optimal. Transformations can be quickly deployed and
transform scheduling, auditing are possibilities. Debugging is
easy and user friendly.
Though the debate continues to rage, more and
more organizations are opting for off the shelf solutions for
ETL. They reason that ETL is an important stage in the process
of creating the data warehouse. It is the process that
determines the integrity and accuracy of data. It is
foolishness to risk data integrity for cutting costs or for
reasons of customization. Off the shelf products have been
tested on a variety of data sources and has enough inbuilt
flexibilities to accommodate customizations.
With the new breed of reasonably priced ETL
tools such as VisualETL, there is even more of a reason to use
an off-the-shelf extract, transform and load software tool.
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