Question

I have below 2 tables

Table1

 Plant      
 -----
 TRP1
 DEP1

Table2

Config
------
84ROC20
100ROC20

and 2 textboxes

1.Start date(datetime) : 2012-08-01 00:00:00.000

2.Enddate(datetime):2012-10-01 00:00:00.000

I want to have below table as a result with 3 columns

Plant  Config    Time
-----  ------   -------
TRP1   84ROC20   2012-08-01 00:00:00.000 
TRP1   84ROC20   2012-09-01 00:00:00.000 
TRP1   84ROC20   2012-10-01 00:00:00.000
DEP1   84ROC20   2012-08-01 00:00:00.000 
DEP1   84ROC20   2012-09-01 00:00:00.000
DEP1   84ROC20   2012-10-01 00:00:00.000
TRP1   100ROC20  2012-08-01 00:00:00.000
TRP1   100ROC20  2012-09-01 00:00:00.000 
TRP1   100ROC20  2012-10-01 00:00:00.000
DEP1   100ROC20  2012-08-01 00:00:00.000 
DEP1   100ROC20  2012-09-01 00:00:00.000
DEP1   100ROC20  2012-10-01 00:00:00.000

Can you please help to have this table

Answer 1

I’m assuming SQL Server 2005+ (using a recursive CTE for convenience), but this should help you out:

-- Get user data
declare @StartDate datetime = '2012-08-01'
declare @EndDate datetime = '2012-10-01'

-- Actual query
;with Dates as ( -- Build a date table based upon the user values
    select @StartDate as DateEntry -- Start at StartDate
    union all
    select dateadd(m, 1, DateEntry) -- Recursively add a month
    from Dates
    where dateadd(m, 1, DateEntry) <= @EndDate -- Until the EndDate is reached
)
select *
from Plant, Config, Dates -- Cross-join all tables to get all possibilities
order by Config desc, Plant desc, DateEntry

This will give the output below for your test data:

Plant      Config     DateEntry
---------- ---------- -----------------------
TRP1       84ROC20    2012-08-01 00:00:00.000
TRP1       84ROC20    2012-09-01 00:00:00.000
TRP1       84ROC20    2012-10-01 00:00:00.000
DEP1       84ROC20    2012-08-01 00:00:00.000
DEP1       84ROC20    2012-09-01 00:00:00.000
DEP1       84ROC20    2012-10-01 00:00:00.000
TRP1       100ROC20   2012-08-01 00:00:00.000
TRP1       100ROC20   2012-09-01 00:00:00.000
TRP1       100ROC20   2012-10-01 00:00:00.000
DEP1       100ROC20   2012-08-01 00:00:00.000
DEP1       100ROC20   2012-09-01 00:00:00.000
DEP1       100ROC20   2012-10-01 00:00:00.000

Essentially, the trick here is to build the Dates table on the fly and then cross-join that with Plant and Config. You could build the Dates table in a variety of other ways, such as with a tally table, cursor, while-loop, in asp.net itself, etc. I like the ease of a recursive CTE here, though I’m assuming a small number of dates need to be generated. More than 100 dates will require that maxrecursion be set, if not picking another method entirely if performance is a problem.