sp_executesql returns different results from view than running the query directly

Question

I'm trying to debug a SSRS report which is showing some dodgy results. I'm using sql profiler I've grabbed the exact query it's running which is executed with exec sp_executesql.

The query is returning results from a view.

If I run the query as it stands including the sp_executesql, I get one set of results. If I grab the query nested inside and run it on it's own, I get a different set of results.

I've got no idea how this is possible. The queries are identical and I was under the impression that sp_executesql simply executes the query.

Is there something I'm missing or how can I debug this further?

exec call looks something like this:

exec sp_executesql N'SELECT FirstName, LastName, DateOfBirth FROM ViewName WHERE
  DateOfBirth >= @pStartDate AND DateOfBirth <= @pEndDate',N'@pStartDate datetime, 
  @pEndDate datetime',@pDate='2010-07-17 00:00:00:000',@pEndDate=''2010-07-17
  23:59:59:000'

If I run that, I get one set of results.

Then if I run:

SELECT FirstName, LastName, DateOfBirth FROM ViewName WHERE 
     DateOfBirth >= '2010-07-17 00:00:00:000' AND
     DateOfBirth <= '2010-07-17 23:59:59:000'

I get a slightly different set of results.

Answer 1

I would try pasting the query as is (doubling the single quotes that is) into the exec sp_executesql and verifying the results are the same as a manual run. If not, then it will be something to do with the date parameter, if the same, then its likely to be some kind of owner / security item.