SSRS Error

Hi All 


I know it should be about project server 2010 but for this im making a small change and i just want to mention a small error that consumed some of my time trying to figure it out in SQL reporting service .


so basically i was creating a custom report for one of our clients , did a small modification on my SQL statement and let the fun begin the error below appeared 

2 hours wasted 

and as you can notice the error message  is not helpful not in any way  but apparently it was an issue with my Query which is running perfectly on SQL and on the query designer retrieving the data with no issues 


my SQL was something like this (just an example) 


SELECT p.TaskDate , p.TaskName , x.TaskDate FROM 


Table1 p JOIN Table2 x on p.TaskDate = x.TaskDate




the query will never have a problem on SQL or with the query designer , 


but the problem is SQL reporting service couldn't handle the same column name generated so you need to use aliases  , just do that and you are good to go 




Cheers hope this will help 
Malek