6. Database Tailoring and Retrofitting Techniques › 6.2 Tailoring the Database › 6.2.1 Tailoring Data Elements › 6.2.1.1 Standard Data Elements › 6.2.1.1.1 Deleting Data Elements
6.2.1.1.1 Deleting Data Elements
There are two facilities available to delete a data element
from a file:
- The timespan indicators on the CA MICS Component
Generator (MCG) NAME statement can be used to delete a
data element from one or more timespans.
- If a data element belongs to a selectable cluster of
data elements, the entire selectable cluster can be
deleted from all timespans of all files within a
component by modifying the MCG OPTION statement.
********************************
* NAME Statement Modifications *
********************************
The example file definition contains the Component Generator
Definition Statements:
...
TYPE N 3 . 3 . 3 .
NAME NCPMNFBL 00 0 0 0 0 0 Free Buffer Low Water Mark
...
Assume that the Free Buffer Low Water Mark had no useful
purpose at your site. If this was the case, this data
element could be eliminated from the file by changing its
NAME statement to:
...
TYPE N 3 . 3 . 3 .
NAME NCPMNFBL 00 N N N N N Free Buffer Low Water Mark
...
This would remove the data element from all timespans in
which the file appears. However, in the case of the NPANCP
file, on which this data element appears, the FILE itself is
not active in the YEARS timespan. In this case,
...
TYPE N 3 . 3 . 3 .
NAME NCPMNFBL 00 N N N N 0 Free Buffer Low Water Mark
...
would accomplish the same end, because the whole file does
not exist in the YEARS timespan, and the data element is not
on any timespan in which the file does exist.
In fact, the data element could be deleted from any timespan
at all. This is based on the timespan indicators on the
NAME statement. For example, there are cases when
...
TYPE N 3 . 3 . 3 .
NAME NCPMNFBL 00 0 N 0 N 0 Free Buffer Low Water Mark
...
would be valid and produce the desired results. There are
cases in which such a specification would cause timespans
other than DETAIL to contain spurious data for NCPMNFBL,
also.
The timespan indicators on the NAME statement for each data
element must consider the timespan indicators on the FILE
statement. If the following combination exists,
FILE ... Y N Y N Y ...
...
NAME ... 0 N 0 N 0 ...
the data element would be summarized properly. The file's
WEEKS timespan would be constructed from summarized DETAIL
data, and the YEARS would be constructed from summarized
DETAIL data. However, the following construction creates
problems:
FILE ... Y Y Y Y Y ...
...
NAME ... 0 N 0 N 0 ...
Code generated by the MCG would cause summarization for the
WEEKS timespans to be driven (summarized) from the DAYS
timespan. The summarization to the YEARS timespan is
driven from the MONTHS timespan of the file.
The DAYS timespan is used as the source of WEEKS and MONTHS
summarization because the DAYS timespan has fewer
observations than the DETAIL timespan, and the summarization
process is more efficient. The same principle causes MONTHS
to be the source of YEARS.
However, if the data element has been dropped from the
timespan from which the new timespan is being summarized,
and the data element is any type other than CALCULATED, the
summarization will be based on SAS missing values, and will
not produce the desired results.
The following combinations of FILE and NAME statement
combinations are valid for data elements that are not
calculated:
FILE timespan indicators NAME timespan indicators
------------------------- ---------------------------------
Y N - Y Y 0 - - 0 - where "-" can be any
0 - - N N valid indicator.
N N N N N
Y N - N N 0 - - - -
N N N N N
Y Y - Y Y 0 0 - 0 -
0 0 - N N
0 N N N N
N N N N N
Y Y - N N 0 0 - - -
0 N N N N
N N N N N
N E - - - - 0 - - -
- N N N N
N N N N N - - - - -
Data elements that are calculated are identified by the data
element type code in the TYPE statement for the type group to
which the data element belongs. Our example is
...
TYPE N 3 . 3 . 3 .
NAME NCPMNFBL 00 0 0 0 0 0 Free Buffer Low Water Mark
...
and the data element is noted as a type N, for minimum.
Calculated data element types are type C, CN, XC, or XCN.
These standard data elements may be dropped from any
timespan by modifying the timespan indicators on the NAME
statement IF the data elements necessary to calculate the
data element's value in its active timespans are present on
those timespans. See the MCG statement section of this
document for more information.
There is one other way to delete a data element. If a data
element is ESSENTIAL, it is active (as marked by the
timespan indicators) even if the ESSENTIAL option is set to
INITIAL or ONLY. See the MCG statement section COMPOPT and
FOPT for more information on the values of the ESSENTIAL
option.
If a data element is ESSENTIAL, it can made nonessential by
changing the NAME statement keyword to NAMX, as follows:
NAME NCPMNFBL 00 0 0 0 0 0 Free Buffer Low Water Mark
becomes
NAMX NCPMNFBL 00 0 0 0 0 0 Free Buffer Low Water Mark
This change causes the data element to be inactive if the
ESSENTIAL options INITIAL or ONLY were used. See the
description of the NAME statement in Section 4.2.4.4.3 for
more information on coding NAMX.
**********************************
* OPTION Statement Modifications *
**********************************
The original form of the NPA component's definition shown
earlier began:
*
* NPA Component generator statements
*
GEN GENFILES
COMP NPA 050 32000 VBS NOACCT NPA Component
TYPE XR 3 . 3 . 3 .
NAME NPANRRLS Receiving Line Speed (line/link)
NAME NPANRSLS Sending Line Speed (line/link)
TYPE XA 5 TIME11.2 6 TIME15.2 6 TIME15.2
NAME NPATMAOT Actual Observation Time
TYPE XR 4 TIME8. 4 TIME8. 4 TIME8.
NAME NPATSEIS Expected Interval Time
NAME NPATSFRU Forward RU Send Time
NAME NPATSLOG Time Record Logged To SMF
AREA NPA NPA Activity Information Area
FILE NCP 00 1 Y Y Y Y N N Y Y NCP Activity File
TYPE R 3 . 3 . 3 .
NAME NCPNRFBQ 00 0 0 0 0 0 Free Buffer Queue Length
NAME NCPNRHQL 00 0 0 0 0 0 NCP Channel Hold Queue Length
NAME NCPNRIQL 00 0 0 0 0 0 NCP Channel Intrmd Queue Len.
NAME NCPNRSFB 00 0 0 0 0 0 Free Buffer Count At Slowdown
TYPE A 5 TIME11.2 6 TIME15.2 6 TIME15.2
NAME NCPTMFCT 00 0 0 0 0 0 Free Cycle Time
NAME NCPTMTIS 00 0 0 0 0 0 Time In Slowdown
...
This component has no selectable data element clusters, and
therefore the standard generator statements do not include an
OPTION statement.
Assume that there is a valid cluster ID called NET1 and its
cluster number is 47. The OPTION statement would be included
in the NPA definition member, and data elements belonging to
the cluster would have a cluster code of 47 coded in their
NAME statements, as follows:
*
* NPA Component generator statements
*
GEN GENFILES
-->OPTION NET1
COMP NPA 050 32000 VBS NOACCT NPA Component
TYPE XR 3 . 3 . 3 .
NAME NPANRRLS Receiving Line Speed (line/link)
NAME NPANRSLS Sending Line Speed (line/link)
TYPE XA 5 TIME11.2 6 TIME15.2 6 TIME15.2
NAME NPATMAOT Actual Observation Time
TYPE XR 4 TIME8. 4 TIME8. 4 TIME8.
NAME NPATSEIS Expected Interval Time
NAME NPATSFRU Forward RU Send Time
NAME NPATSLOG Time Record Logged To SMF
AREA NPA NPA Activity Information Area
FILE NCP 00 1 Y Y Y Y N N Y Y NCP Activity File
TYPE R 3 . 3 . 3 .
NAME NCPNRFBQ 00 0 0 0 0 0 Free Buffer Queue Length
-->NAME NCPNRHQL 47 0 0 0 0 0 NCP Channel Hold Queue Length
-->NAME NCPNRIQL 47 0 0 0 0 0 NCP Channel Intrmd Queue Len.
NAME NCPNRSFB 00 0 0 0 0 0 Free Buffer Count At Slowdown
...
Deleting the entire cluster can be accomplished by changing
the OPTION keyword NET1 to NONET1. All data elements that
belong to the cluster (including NCPNRHQL and NCPNRIQL) would
be deleted from all timespans of all files in the NPA
Component:
*
* NPA Component generator statements
*
GEN GENFILES
-->OPTION NONET1
COMP NPA 050 32000 VBS NOACCT NPA Component
...
See the individual product guides for a list of cluster names
used in a specific cccGENIN member.
****************************
* Making the Modifications *
****************************
To delete a data element from one or more timespans, if the
data element is not a sequence data element in the file,
perform the following:
- Modify the timespan indicators on the NAME statement
for that data element, if necessary.
- Modify the option selection codes on the OPTION
statement, if necessary.
- Run the component generation for the component in
question.
- Drop the data element from the file in the desired
timespan(s) since the next daily update for any
database unit in which the component has been installed
reflects the change.
To delete a data element from one or more timespans if
the data element IS a sequence data element in the file, see
the sections in this chapter on modifying the sequence of a
file. Modify the sequence, and follow the instructions above
to delete the data element.
