Question

I have a SQL query that takes a date and reports number of pallets that have been scanned into a depot over the last 7 days, but not scanned out by the given date. It takes about a second to run. I need to report this number (using an SSRS report) for the last 14 days. However – when I create either a CTE or a temporary table to generate the dates to report on, instead of rising to 10 seconds (for about 10 dates), it rises to over 3 minutes!

Please advise.

Here’s the single date report:

DECLARE @back integer
SET @back = 7
Declare @testDate DateTime
SET @testDate = '2012-10-09'
--opening balance query
select count(p.PalletID) as Opening_Balance
FROM [POSTALE].[dbo].[Pallet] p
join [POSTALE].[dbo].[Tracking] t on t.PalletID = p.PalletID
--scan was before indicated day
where CAST(DateAdd(hour, -6, t.TrackDateTime) as DATE) <= @testDate
--scan was after number of days to look back
and CAST(DateAdd(hour, -6, t.TrackDateTime) as DATE) >= dateadd(day, 0 - @back, @testDate)
--scanned into hub (get only the earliest occurence)
and t.TrackingID = (select top 1 tr.TrackingID from [POSTALE].[dbo].[Tracking] tr 
                where tr.TrackCode in ('SCAN OFF TRUNK HUB', 'DAYS') 
                and tr.PalletID = t.PalletID order by tr.TrackingID)
--not scanned out of hub by the indicated day
and (select count(tr.TrackingID) from [POSTALE].[dbo].[Tracking] tr where t.PalletID = tr.PalletID and 
    CAST(DateAdd(hour, -6, tr.TrackDateTime) as DATE) <= @testDate and tr.TrackCode in 
    ('SCAN ONTO TRUNK DEPOT', 'SCAN OFF TRUNK DEPOT', 'SECURITY SCAN AT DEPOT', 'SCAN OFF TRUNK DEPOT', 'SCANNER BROKEN',
    'SCAN ON DEPOT VEHICLE', 'POD ADDED','NO POD ADDED')) = 0

Here’s the code to join it with a CTE:

DECLARE @back integer
SET @back = 7
declare @start_date as date;
set @start_date = cast(getdate() - 14 as date);
declare @end_date as date;
set @end_date = cast(getdate() as date);
WITH DateList AS
(
    SELECT @start_date AS start_date
    UNION ALL
    SELECT DATEADD(DAY, 1, start_date)
    FROM DateList
    WHERE DATEADD(DAY, 1, start_date) < @end_date
)
SELECT
    (select count(p.PalletID) as Opening_Balance
...
,datediff(DAY, d.start_date, getdate()) as daysBack
from DateList d
order by d.start_date

..and here’s the temp table version:

DECLARE @back integer
SET @back = 7
--hours into day that get pushed back to previous day
DECLARE @dayStart integer
set @dayStart = 12
--today + 12 hours as datetime
Declare @date12 as datetime
set @date12 = DateAdd(hour, @dayStart, cast(cast(getdate() as date) as datetime))
--temporary table to create list of dates to report on
DECLARE @DateList TABLE(
        DayDate DateTime
)
insert into @DateList (DayDate) Select DateAdd(day, - 14, @date12) where datepart(weekday, getdate() - 14) <> 7 and datepart(weekday, getdate() - 14) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 13, @date12) where datepart(weekday, getdate() - 13) <> 7 and datepart(weekday, getdate() - 13) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 12, @date12) where datepart(weekday, getdate() - 12) <> 7 and datepart(weekday, getdate() - 12) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 11, @date12) where datepart(weekday, getdate() - 11) <> 7 and datepart(weekday, getdate() - 11) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 10, @date12) where datepart(weekday, getdate() - 10) <> 7 and datepart(weekday, getdate() - 10) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 9, @date12) where datepart(weekday, getdate() - 9) <> 7 and datepart(weekday, getdate() - 9) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 8, @date12) where datepart(weekday, getdate() - 8) <> 7 and datepart(weekday, getdate() - 8) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 7, @date12) where datepart(weekday, getdate() - 7) <> 7 and datepart(weekday, getdate() - 7) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 6, @date12) where datepart(weekday, getdate() - 6) <> 7 and datepart(weekday, getdate() - 6) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 5, @date12) where datepart(weekday, getdate() - 5) <> 7 and datepart(weekday, getdate() - 5) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 4, @date12) where datepart(weekday, getdate() - 4) <> 7 and datepart(weekday, getdate() - 4) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 3, @date12) where datepart(weekday, getdate() - 3) <> 7 and datepart(weekday, getdate() - 3) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 2, @date12) where datepart(weekday, getdate() - 2) <> 7 and datepart(weekday, getdate() - 2) <> 1
insert into @DateList (DayDate) Select DateAdd(day, - 1, @date12) where datepart(weekday, getdate() - 1) <> 7 and datepart(weekday, getdate() - 1) <> 1
SELECT
    (select count(p.PalletID) as Opening_Balance
...
,datediff(DAY, d.DayDate, getdate()) as daysBack
from @DateList d
order by d.DayDate

Answer 1

You haven’t described your indexing which could obviously be a huge factor, but one thing I noticed is that your WHERE clause has elements that are not sargable and could be.

For example, try changing:

where CAST(DateAdd(hour, -6, t.TrackDateTime) as DATE) <= @testDate 

to

where t.TrackDateTime < dateadd(hour, 6, dateadd(day, 1, @testDate))

You’ll need to do a similar thing with this line:

and CAST(DateAdd(hour, -6, t.TrackDateTime) as DATE) >= dateadd(day, 0 - @back, @testDate)