Using and working with Impact Factor


Note that Impact Factor is ONLY used when the measurement mode is set to Enhancement Function Points (EFP) in the CAST Management Studio. If the mode is set to the default Automated Enhancement Points (AEP) then a read-only Complexity Factor is used instead.

An Impact Factor is a value that is applied to a Transactional Function or a Data Function. By default, all Transactional Functions / Data Functions are given a default Impact Factor value of 1.0 - this can be seen in the Enhancement node - Right hand panel by selecting either the Data Function or the Transactional Functions sub node:

The EFP (Enhancement Function Points) value of a Transaction is derived from the multiplication of the Impact Factor and the EFP value (IF x EFP = EFP) - therefore, by manually modifying the Impact Factor value up or down (based on whether a change in the Transactional Function / Data Function is high or low impact) it is possible to influence the resulting EFP value.

Take the following example for Transactional Functions. All items are using the default 1.0 Impact Factor value:

Then, the Impact Factor value is changed to 0.4 for all DELETED Transactional Functions. The result is that the EFP value has been changed to 3 (0.4 x 7 = 2.8, rounded to 3):

Implementing custom Impact Factor values

The CAST Dashboard Service is delivered with three empty SQL procedures that will be executed (when a custom option is set to do so) during the snapshot generation process. The code in the SQL procedures will cause the Impact Factor value to be changed.

Implementing custom Impact Factor values is a multi-step process, described below:

1) Enabling the custom option to call the SQL procedures

To call the SQL procedures during the snapshot generation, you must first enable (set to ON) a custom option in the Dashboard Service.

CSS
/* Replace <name_of_Dashboard_Service> with the name of your Dashboard Service schema */set search_path=<name_of_Dashboard_Service>;select set_tcc_option_fpcustom (1,1)
Oracle
declare returnCode int =0;beginreturnCode = SET_TCC_OPTION_FPCUSTOM (1,1);end;
MS SQL Server
exec SET_TCC_OPTION_FPCUSTOM  1,1

Each of the above options will cause a new line to appear in the SYS_SITE_OPTIONS table when running the following query:

select * from SYS_SITE_OPTIONS where OPTION_NAME = 'TCC_FP_EXECCUSTOM_STEPS'

Result:

"TCC_FP_EXECCUSTOM_STEPS";"TRACE_ON"

2) Disabling the custom option to call the SQL procedures

If you no longer require the SQL procedure, then run the following queries:

CSS
/* Replace <name_of_Dashboard_Service> with the name of your Dashboard Service schema */set search_path=<name_of_Dashboard_Service>;select SET_TCC_OPTION_FPCUSTOM (0,0)
Oracle
declare returnCode int =0;beginreturnCode = SET_TCC_OPTION_FPCUSTOM (0,0);end;
MS SQL Server
exec SET_TCC_OPTION_FPCUSTOM  0,0

This will remove the option from the SYS_SITE_OPTIONS table:

select * from SYS_SITE_OPTIONS where OPTION_NAME = 'TCC_FP_EXECCUSTOM_STEPS'

Result:

no results

3) SQL Procedures

The three empty SQL procedures can be found in the Dashboard Service - each one corresponds to the state that a Transactional Function/Data Function can be in (there is no SQL procedure for the UNCHANGED status):

Type Name Status Table To Update
Data Function EFP_USR_IF_DEL_DF_RULE DELETED EFP_DF_Info
Data Function EFP_USR_IF_MOD_DF_RULE MODIFIED EFP_DF_Info
Data Function EFP_USR_IF_ADD_DF_RULE ADDED EFP_DF_Info
Transactional Function EFP_USR_IF_DEL_TF_RULE DELETED EFP_Tran_Info
Transactional Function EFP_USR_IF_MOD_TF_RULE MODIFIED EFP_Tran_Info
Transactional Function EFP_USR_IF_ADD_TF_RULE ADDED EFP_Tran_Info

4) Table to update for the Impact Factor

The Impact Factor value is available for all Transactional Functions/Data Functions of a given snapshot. It is stored in two tables (one for Transactional Functions, one for Data Functions) in the CAST Dashboard Service. The tables are described below:

Data Functions - EFP_DF_Info

column Name description type Information How to use
Snapshot_ID The Snapshot Id Integer not null READ-ONLY
Object_ID Data Function Id : : to find the name join the table DSS_OBJECTS Integer not null READ-ONLY
Object_Checksum Data Function Checksum Integer not null READ-ONLY
Impact_Factor Data Function Impact Factor Float not null , DEFAULT = 1.0 READ-WRITE can be updated by CUSTOM CODE
Status Data Function Status: ADDED, MODIFIED, DELETED, UNCHANGED String Computed by the snapshot READ-ONLY

Transactional Functions - EFP_Tran_Info

Column Name Description Type Information How to use
Snapshot_ID The Snapshot Id Integer not null READ-ONLY
Object_ID Transaction Id : : to find the name join the table DSS_OBJECTS Integer not null READ-ONLY
Object_Checksum Transaction Checksum Integer not null READ-ONLY
Impact_Factor Transaction Impact Factor Float not null , DEFAULT = 1.0 READ-WRITE can be updated by CUSTOM CODE
Status Transaction Status: ADDED, MODIFIED, DELETED, UNCHANGED String Computed by the snapshot READ-ONLY

5) How to implement the SQL procedures

To implement the custom code to modify the Impact Factor, you need to edit the correct function corresponding to the specific status you want to update - i.e. use the EFP_USR_IF_DEL_TF_RULE procedure if you want to change the Impact Factor of Transactional Functions with the status DELETED and use the EFP_USR_IF_DEL_DF_RULE procedure if you want to change the Impact Factor of Data Functions with the status DELETED. You must update the impact factor based on a defined scope and condition.

The Update Clause should always contain the two following rows:

Snapshot_ID= I_SNAPSHOT_ID --> this is the parameter of the proc
and Status = <APPROPRIATE_STATUS> --> this is the one on the name of the proc

Example - to set the Impact Factor = 0.40 for all DELETED Transactional Functions of the snapshot. The SQL procedure to update is EFP_USR_IF_DEL_TF_RULE:

CREATE OR REPLACE FUNCTION EFP_USR_IF_DEL_TF_RULE( I_SNAPSHOT_ID int, I_CUSTOM_TRACE int)RETURNS integer AS$BODY$DECLARE L_ERRORCODE INTEGER DEFAULT 0;L_ROWCOUNT int := 0 ;Begin if ( I_CUSTOM_TRACE > 0 ) then perform cast_log('TCC-FP-CUSTOM- EFP_USR_IF_DEL_TF_RULE for I_SNAPSHOT_ID ' || to_char(I_SNAPSHOT_ID)); end if;--************** THE CUSTOM CODE STARTS BELOW ****************-update EFP_Tran_Infoset Impact_Factor = 0.40Where Snapshot_ID = I_SNAPSHOT_ID and Status = 'DELETED' ;Get Diagnostics L_ROWCOUNT := Row_Count; if ( I_CUSTOM_TRACE > 0 ) then perform cast_log('TCC-FP-CUSTOM- EFP_USR_IF_DEL_TF_RULE for I_SNAPSHOT_ID ' || to_char(I_SNAPSHOT_ID)|| ' update the Impact factor 0.40 for count : ' || to_char(L_ROWCOUNT)); end if; --************** THE CUSTOM CODE ENDS HERE ****************-Return L_ERRORCODE;END;$BODY$LANGUAGE plpgsql;

If the custom option is set to ON, then when the snapshot is generated the EFP_USR_IF_DEL_TF_RULE procedure containing the above query will be executed. The Impact Factor is set for DELETED Transactional Functions in the Dashboard Service and the resulting EFP is adjusted by the Impact Factor.

Notes


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