3. CAPACITY PLANNING DATABASE › 3.5 Business Element Files › 3.5.1 Usage Guidelines

3.5.1 Usage Guidelines

 
The term "business element" is used to represent a
measurement unit that characterizes activity in any specified
division of an organization.  The objective of a business
element forecast is to investigate possible statistical
relationships between such measurements and the demand for
computer resources.

The business element files represent business element values
for your installation at either the DAYS, WEEKS or MONTHS
timespan.   Because interest in specific business elements
varies from installation to installation, all but one of the
data elements contained in a business element file must be
user-defined.

The DATE data element is the exception.  This data element
must always be present in a business element file.  It is the
end date of the interval (that is, day, week, or month)
represented by the record.  The business element file
database generation routines automatically calculate and
maintains two additional data elements for you: YEAR and
MNTHDAY/WEEK/MONTH (depending on the timespan that you
define).  You can define the remainder of the data elements
in the business element file using the Business Element File
Definition screen (see Figure 3-122).

As with the resource element files, you can define any number
of business element files.  You supply a three-character that
identifies each business element file definition.  This name
must be unique.

The Capacity Planning database file contains two types of
business element files.  The first type contains observed
values of historical data.  The second type stores forecasts
generated by the univariate or multivariate software.  Each
type of file is also defined using multiple cycles.
 
Cycle 01:    Data from the last file load or update plus any
             data from the existing 01 cycle that is not
             older than allowed by the Maximum data available
             for analysis parameter on the Business Element
             File Definition screen shown in Figure 3-122.
             The CAPxxx01 File contains user-supplied
             observations, while the CPFxxx01 File contains
             forecasted observations from the workload
             forecasting routines.  As with the resource
             element files, the CPFxxxnn File is not created
             until you generate and save a forecast for the
             first time.

Cycle 02:    Data that is contained in the Cycle 01 File
             when it is aged.  Aging occurs before the Cycle
             01 File is loaded or updated.  The Cycle 02 File
             acts as a backup copy of the Cycle 01 File as it
             existed before the last file update.

Cycle 03     A copy of the data from the Cycle xx-1 File just
through      before it is aged.  This occurs each time the
Cycle nn:    Cycle 01 File is updated.

The Cycle 01 File is the input file for the analysis and
forecasting programs.  It is created the first time you
execute the file definition inquiry.  This process reads the
business elements that you define either from an externally
created data set or from a SAS/FSP session.

Note that the historical files (CAP files) and the forecast
files (CPF files) are not aged together.  The CAP files are
aged whenever you perform a file update.  You can age the CPF
files only when you request aging through a parameter on the
workload forecast control screen.

In addition to the data elements defined for the business
element files containing the observations that you provide
(the CAPxxxnn files), the forecast files (CPFxxxnn files)
contain three additional data elements:
 
FILE_NO:     The types of forecast data from the workload
             forecasting routines.  If FILE_NO is 11, the
             data values are point estimates.  If FILE_NO is
             12, the data values are confidence limits.

FORYEAR:     The year value of the most recent historical
             observation used to derive the forecast.  For
             example, if you specify to Univariate Model
             Forecasting that a forecast is to be generated
             based on data from June 1998 through October
             1999, the value of FORYEAR would be 99.  This
             data element containing this value would be
             present on each of the observations that are
             forecasted during that execution of Univariate
             Model Forecasting.

FORMNDY/     The day, week, or month value of the most recent
FORWEEK/     historical observation used to derive the
FORMONTH:    forecast.  For example, if you specify to
             Univariate Model Forecasting that a monthly
             forecast is to be generated based on data from
             June 1998 through October 1999, the value of
             FORMONTH would be 10.  This data element
             containing this value would be present on each
             of the observations that are forecasted during
             that execution of Univariate Model Forecasting.

Two methods are supported for entering your business element
observations into the business element file.  These methods
are identified on the Business Element File Data Entry screen
shown in Figure 3-125.

With the first method, you enter the observations directly
into the business element file via a SAS/FSP session invoked
for you by the business element file database generation
routines.  If you select this method, you first need to
initialize the business element file by selecting Option 1 on
the Business Element File Data Entry screen.

The initialization process places a number of entries into
the file that contains values for the DATE and YEAR and
MNTHDAY/WEEK/MONTH data elements, and leaves your remaining
business data elements with missing values.  You specify the
number of initialized entries and the starting date for the
first initialized entry.  Once you initialize the file, you
can enter data values as often as you want into the
initialized entries by selecting Option 2 on the Business
Element File Data Entry screen.  Should you eventually need
more entries than you first initialized, you can add them
using the normal SAS/FSP commands that are available for this
function.

The second method of entering your business element
observations is to build an external file (not a SAS file)
containing the values for the business elements.  An easy
method of doing this is to invoke the ISPF Editor and enter
the data values directly into a sequential file or into a
member of a partitioned data set.  Then select Option 3 on
the Business Element File Data Entry screen to read the data
directly into your business element file from the input file
you specify.  If you use this method, you do not have to
initialize the file.