Running Multiplication in T-SQL

Question

GTS Table

CCP months   QUART   YEARS  GTS
----  ------  -----    ----- ---
CCP1    1       1   2015    5
CCP1    2       1   2015    6
CCP1    3       1   2015         


        

Answer 1

Im not sure if the question is how do the over() logic or perform a recursive cte in 2012 or just calculate in 2012 without recursive cte.

Looks like you were trying to create the PRODUCT() agreggation equivalent. But as I put in my comment

The function 'Exp' is not a valid windowing function, and cannot be used with the OVER clause.

So I did my version without recursive cte for my answer. I include one aditional year on the sample data with different baseline

• Calculate the total gts for each Quart
• Get the baseline from first Quart
• Calculate the base line for the other Quart doing the dummy PRODUCT() aggregated

SQL Fiddle Demo

WITH gtsTotal as (
    SELECT [CCP], [Year], [QUART], SUM([GTS]) as sumGts
    FROM gts
    GROUP BY [CCP], [Year], [QUART]
), 
newBase as (
    SELECT g.[CCP],  g.[YEAR],  b.[BASELINE], 1 as sQuart, b.[BASELINE] as [TotalBase]
    FROM gtsTotal g
    INNER JOIN baseline b
       on g.[Year] = b.[YEARS]          
      and g.[CCP] = b.[CCP]
    WHERE g.[QUART] <= 1
    UNION ALL
    SELECT g.[CCP],  g.[YEAR],  b.[BASELINE], MAX(g.[QUART]) + 1 as sQuart, (Exp(Sum(Log(sumGts))) * b.[BASELINE]) as [TotalBase]
    FROM gtsTotal g
    INNER JOIN baseline b
       on g.[Year] = b.[YEARS]          
      and g.[CCP] = b.[CCP]        
    WHERE g.[QUART] <= 1
    GROUP BY g.[CCP],  g.[YEAR], b.[BASELINE]
            UNION ALL
    SELECT g.[CCP],  g.[YEAR],  b.[BASELINE], MAX(g.[QUART]) + 1 as sQuart, (Exp(Sum(Log(sumGts))) * b.[BASELINE]) as [TotalBase]
    FROM gtsTotal g
    INNER JOIN baseline b
       on g.[Year] = b.[YEARS]          
      and g.[CCP] = b.[CCP]        
    WHERE g.[QUART] <= 2
    GROUP BY g.[CCP],  g.[YEAR], b.[BASELINE]
            UNION ALL
    SELECT g.[CCP],  g.[YEAR],  b.[BASELINE], MAX(g.[QUART]) + 1 as sQuart, (Exp(Sum(Log(sumGts))) * b.[BASELINE]) as [TotalBase]
    FROM gtsTotal g
    INNER JOIN baseline b
       on g.[Year] = b.[YEARS]          
      and g.[CCP] = b.[CCP]        
    WHERE g.[QUART] <= 3
    GROUP BY g.[CCP],  g.[YEAR], b.[BASELINE]
)
SELECT g.CCP, g.months, g.QUART, g.Year, CEILING(g.GTS * n.TotalBase)
FROM newBase n
INNER JOIN gts g
   ON n.CCP = g.CCP
  AND n.[Year] = g.[Year]
  AND n.[sQuart] = g.[QUART]
order by g.[Year], n.sQuart

Output

|  CCP | months | QUART | Year | Result|
|------|--------|-------|------|-------|
| CCP1 |      1 |     1 | 2015 |    25 |
| CCP1 |      2 |     1 | 2015 |    30 |
| CCP1 |      3 |     1 | 2015 |    35 |
| CCP1 |      4 |     2 | 2015 |   360 |
| CCP1 |      5 |     2 | 2015 |   180 |
| CCP1 |      6 |     2 | 2015 |   180 |
| CCP1 |      7 |     3 | 2015 |  2160 |
| CCP1 |      8 |     3 | 2015 |  1440 |
| CCP1 |      9 |     3 | 2015 |   720 |
| CCP1 |     10 |     4 | 2015 |  8640 |
| CCP1 |     11 |     4 | 2015 | 12960 |
| CCP1 |     12 |     4 | 2015 | 17280 |