Code explanation

[#1]

Kindly could any one explain me the ! back end Code  which already writen in ytd creation qvd

LET vStartDate = Num(AddMonths(YearStart(Today()),-24));

LET vEndDate = Num(AddMonths(YearEnd(Today()), 0));

PERIODT:

Load Distinct

  Date(MonthEnd(($(vStartDate) +(Iterno()-1))), 'MMM-YYYY') as PERIOD

Autogenerate(1)

While

  Date($(vStartDate)+(Iterno()-1)) <=Date($(vEndDate));

  PERIOD:

Load Distinct RowNo() as PERIOD_KEY, PERIOD,

  Year(PERIOD) as YEAR,

  Month(PERIOD) as MONTH

  resident PERIODT order by PERIOD

  ;

  DROP table PERIODT;

TYPE:

LOAD TYPE_KEY,

     [TIME ANALYSIS]

FROM

(ooxml, embedded labels, table is Sheet1);

SUB LOAD_nAGO(vTypeTemporel, vOffset)

REL_PER_TIME:

LOAD PERIOD_KEY,

PERIOD_KEY-$(vOffset) as TIME_KEY,

'$(vTypeTemporel)' as TYPE_KEY

RESIDENT PERIOD

where PERIOD_KEY > $(vOffset);

End sub

call LOAD_nAGO('CURRENT', 0);

call LOAD_nAGO('P-1', 1);

call LOAD_nAGO('Y-1', 12);

SUB LOAD_MVTOT(vTypeTemporel, vNbPeriods, vOffset);

// F. AUNEZ, sep 2013

// Population of the relation PERIODE - TIME

// Creation of the moving totals (and averages ...)

//

Concatenate (REL_PER_TIME)

LOAD

PERIOD_KEY,

PERIOD_KEY + 1 - IterNo()-$(vOffset) as TIME_KEY,

'$(vTypeTemporel)' as TYPE_KEY

Resident PERIOD

while IterNo() <= $(vNbPeriods) AND PERIOD_KEY >= $(vNbPeriods)+$(vOffset)

;

END SUB

call LOAD_MVTOT ('MVTOT3', 3, 0)

call LOAD_MVTOT ('MVTOT12', 12, 0);

call LOAD_MVTOT ('MVTOT3 Y-1', 3, 12);

call LOAD_MVTOT ('MVTOT12 Y-1', 12, 12);

SUB LOAD_YTD(vTypeTemporel, vOffset);

// F. AUNEZ, sep 2013

// Population of the relation PERIODE - TIME

// Creation of the YTD

//

//June 2013 (key 18) will totalize from January (Key 13) to June (Key 18)

// For the YTD Year Ago, same totalization but for the Year Ago (12 keys back)

// we will use Iter() in order to loop back until Janyary (Key 1, 13, 25 ...)

// that what the div( ....) part does

Concatenate (REL_PER_TIME)

LOAD

PERIOD_KEY,

PERIOD_KEY + 1 - IterNo() - $(vOffset) as TIME_KEY,

'$(vTypeTemporel)' as TYPE_KEY

Resident PERIOD

while PERIOD_KEY - $(vOffset)-IterNo()+1 >= div( if( mod(PERIOD_KEY- $(vOffset),

12)=0, PERIOD_KEY- $(vOffset)-1, PERIOD_KEY- $(vOffset)), 12)*12 +1

;

END SUB

call LOAD_YTD('YTD', 0);

call LOAD_YTD('YTD-1', 12);