One issue with stored procedures in reporting services is that if the stored procedure is quite complex, e.g. has multiple select statements, that SSRS has trouble parsing them correctly to determine the columns.
Very true. You may have a SP with branched logic.. IE...
If @var <5
-- do something
select col1, col2, col3
else if @var>=5 <10
--do something else
select col1, col2, col3, col4
else
--do this instead
select col1, col2, col3, col4, col5
This creates confusion when SSRS is trying to create the dataset columns.
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