Many data marts were initially quite successful because they fulfilled
a specific business need relatively quickly.
However, problems began to surface. There was often no coordination between
departments regarding basic definitions, such as ???customer.??? If a senior manager
asked the same question of multiple departments, the answers provided by these
independent data marts were often different, thus calling into question the validity of
all of the marts. Many departments also encountered ongoing difficulty in managing
these multiple data marts and in maintaining extractions from operational sources
(which were often duplicated across multiple departments).
As architects took another look at their solutions, they began to realize that it was
very important to have a consistent view of the detailed data at an enterprise data
warehouse level. They also saw that data marts could solve business problems and
provide return on investment in an incremental fashion. Today, most successful
implementers simultaneously grow dependent data marts one business solution at a
time while growing the enterprise warehouse server in an incremental fashion.
Pages:
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497