Question

I’m new to stored procedures and am trying to create one for a school project. I wrote an SQL statement that does what I want and just converted it to a stored procedure (probably a bad hack job, but we’re running out of time and have tons of others things to do). We’re using aspnet Membership Services and the entire built-in database.

What I want to do
I’m using 1 table (TimesheetEntry). I want to get all the timesheets of all the employees, sum the hours per weekday to get hours/week and repeat this for the past 4 weeks (week1-week4 below) and for the past 4 months (month1-month4) below. I used nested select statements to do this.

Here is the full error message:

Error 217: Maximum stored procedure, function, trigger, or view nesting level exceeded (limit 32).

Here is the full Stored Procedure:

CREATE PROCEDURE sp_GetTimesheetSummaryReport2
@dateFor DATETIME
AS
SELECT CONVERT(VARCHAR, DATEADD(DAY, -7, GETDATE()), 111) AS startDate,
    CONVERT(VARCHAR, GETDATE(), 111) AS currentDate,
    projId, wpId, empId, 
    (
        SELECT (SUM(mon) + Sum(tue) + Sum(wed) + Sum(thu) + SUM(fri) + SUM(sat) + SUM(sun)) AS Week
        FROM TimesheetEntry
        WHERE empId = t.empId AND tsDate BETWEEN @dateFor AND DATEADD(DAY, -7, @dateFor)
        GROUP BY empId, projId, wpId
    ) AS week1,
    (
        SELECT (SUM(mon) + Sum(tue) + Sum(wed) + Sum(thu) + SUM(fri) + SUM(sat) + SUM(sun)) AS Week
        FROM TimesheetEntry
        WHERE empId = t.empId AND tsDate BETWEEN DATEADD(DAY, -7, @dateFor) AND DATEADD(DAY, -14, @dateFor)
        GROUP BY empId, projId, wpId
    ) AS week2,
    (
        SELECT (SUM(mon) + Sum(tue) + Sum(wed) + Sum(thu) + SUM(fri) + SUM(sat) + SUM(sun)) AS Week
        FROM TimesheetEntry
        WHERE empId = t.empId AND tsDate BETWEEN DATEADD(DAY, -14, @dateFor) AND DATEADD(DAY, -21, @dateFor)
        GROUP BY empId, projId, wpId
    ) AS week3,
    (
        SELECT (SUM(mon) + Sum(tue) + Sum(wed) + Sum(thu) + SUM(fri) + SUM(sat) + SUM(sun)) AS Week
        FROM TimesheetEntry
        WHERE empId = t.empId AND tsDate BETWEEN DATEADD(DAY, -21, @dateFor) AND DATEADD(DAY, -28, @dateFor)
        GROUP BY empId, projId, wpId
    ) AS week4,
    (
        SELECT (SUM(mon) + Sum(tue) + Sum(wed) + Sum(thu) + SUM(fri) + SUM(sat) + SUM(sun)) AS Month
        FROM TimesheetEntry
        WHERE empId = t.empId AND MONTH(tsDate) = MONTH(@dateFor)
        GROUP BY empId, projId, wpId
    ) AS month1,
    (
        SELECT (SUM(mon) + Sum(tue) + Sum(wed) + Sum(thu) + SUM(fri) + SUM(sat) + SUM(sun)) AS Month
        FROM TimesheetEntry
        WHERE empId = t.empId AND MONTH(tsDate) = MONTH(DATEADD(MONTH, -1, @dateFor))
        GROUP BY empId, projId, wpId
    ) AS month2,
    (
        SELECT (SUM(mon) + Sum(tue) + Sum(wed) + Sum(thu) + SUM(fri) + SUM(sat) + SUM(sun)) AS Month
        FROM TimesheetEntry
        WHERE empId = t.empId AND MONTH(tsDate) = MONTH(DATEADD(MONTH, -2, @dateFor))
        GROUP BY empId, projId, wpId
    ) AS month3,
    (
        SELECT (SUM(mon) + Sum(tue) + Sum(wed) + Sum(thu) + SUM(fri) + SUM(sat) + SUM(sun)) AS Month
        FROM TimesheetEntry
        WHERE empId = t.empId AND MONTH(tsDate) = MONTH(DATEADD(MONTH, -3, @dateFor))
        GROUP BY empId, projId, wpId
    ) AS month4
FROM TimesheetEntry t
GROUP BY t.empId, t.projId, t.wpId
ORDER BY t.projId, t.wpId, t.empId;

EXECUTE sp_GetTimesheetSummaryReport '2011/02/01';

My questions

1. Why am I getting this error? Have I
   exceeded the stack, are there too
   many stored
   procedures/triggers/functions in the
   database, is my nesting too deep?

2. How can I solve it? Is my stored
   procedure so terrible that I should
   restart using a better syntax?

Answer 1

I’m still not seeing any recursion. To simplify your query, might I recommend making:

totalhours AS (mon + tue + wed + thu + fri + sat + sun) PERSISTED

into a computed column (perhaps persisted) in your table. Then you aren’t either repeating the logic nor invoking an expensive user-defined function, yet getting some better maintainability.

It then gives:

    SELECT (SUM(totalhours)) AS Week
    SELECT (SUM(totalhours)) AS Month

I also noticed your query has things like:

(
    SELECT (SUM(totalhours)) AS Week
    FROM TimesheetEntry
    WHERE empId = t.empId AND tsDate BETWEEN @dateFor AND DATEADD(DAY, -7, @dateFor)
    GROUP BY empId, projId, wpId
) AS week1,

Which will return an error if there is more than one row – i.e. if an emp has more than one proj or wp. Because you are treating this as a correlated scalar subquery.