Slow in the Application, Fast in SSMS? Understanding Performance Mysteries
When I read various forums about SQL Server, I frequently see questions from deeply mystified posters. They have identified a slow query or stored procedure in their application. They cull the SQL batch from the application and run it in SQL Server Management Studio (SSMS) to analyse it, only to find that the response is instantaneous. At this point they are inclined to think that SQL Server is all about magic. A similar mystery is when a developer has extracted a query in his stored procedure to run it stand-alone only to find that it runs much faster – or much slower – than inside the procedure.