Information Technology Reference
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If all of these application capabilities pass the tests, then the fi nal evaluation
focuses on the maximum fi le size the database management package will build and
maintain. The database package vendor may claim maximum fi le size support be-
yond the application requirements. It is prudent business to actually test the database
package against the application requirements if the evaluator (CPI in this case) has
not seen that the database package supports fi les that are large elsewhere.
The maximum fi le size testing process is straightforward and will run many
hours. The tactic is to write a simple program that adds dummy records to a database
fi le through the database management package's ADD function. The dummy records
have a unique record ID started at 1 and incremented by 1 until the desired number
of records have been stored based on the estimated maximum number of records
required for the new application. The dummy records can all be blank but should
approximate the expected record size for the new application. Anticipate fi le test
problems if your maximum number of records or maximum fi le size parameters are
within 10% of the database vendor's published maximums. Commercial software
does not have a sterling track record when marketing claims meet technology
boundaries.
The database management software preferred by CPI is evaluated fi rst and soon
rejected because the wysiwyg (pronounced “wizzy wig,” standing for “what you see
is what you get”) report design tool of that software package cannot keep the print
registered on the blank DSA certifi cation form as the printing proceeded down the
form. The second choice database management system has less sophisticated devel-
opment tools (no on-screen report designers or screen designers), but it keeps the
printing registered within the entire length of the blank certifi cation form. The sec-
ond choice database management package candidate also provides all the remaining
required capabilities as verifi ed through developer and tester execution.
The search for appropriate workstation hardware is easier than the database
management software search because the workstation capabilities are commonly
available off-the-shelf. Pricing rather than capability of comparable workstations
becomes the workstation hardware selection yardstick.
13.4.2 ApplicationLogicalDesign
While the database management software and workstation hardware are being eval-
uated, CPI also starts the logical design of the application. This is possible because
the logical design is dependent neither on the choice of database management soft-
ware nor the workstation hardware. The fi rst draft of the logical design is refl ected in
the Case Study B Design stage primary document about the user interface. As each
logical design component is completed, the CPI development team walks (static test-
ing) the CPI testing team through the design component to verify that it fulfi lls the
associated requirements.
Only some of the components in the new system are included in the user inter-
face design. The CPI developers choose representative components to design fi rst.
After the developers get confi rmation from DSA and the testing team that the logical
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