jonathan.crawford - Wednesday, February 21, 2018 2:48 PM
This is a parameter sniffing related issue - and that can solve the performance problem. It would also indicate to me that there are two (or more) plans for that procedure - one for logging into SSMS and a separate one coming from SSRS.
You can also get separate execution plans by simply using a different login/user. If the objects in the code are not schema qualified - and each user has a different default schema defined then a separate execution plan will be generated for each user schema that calls the procedure.
Jeffrey Williams
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