I have an EMPLOYEE table in a SQL Server 2008 database which stores information for employees (~80,000+) many times for each year. For instance, there could by 10 different instances of each employees data for different years.
I’m reporting on this data via a web app, and wanted to report mostly with queries directly against the EMPLOYEE table, using functions to get information that needed to be computed or derived for reporting purposes.
These functions sometimes have to refer to an EMPLOYEE_DETAIL table which has 100,000+ rows for each year – so now that I’m starting to write some reporting-type queries, some take around 5-10 seconds to run, which is a bit too slow.
My question is, in a situation like this, should I try and tune functions and such so I
can always query the data directly for reporting (real-time), or is a better approach to summarize the data I need in a static table via a procedure or saved query, and use that for any reporting?
I guess any changes in reporting needs could be reflected in the “summarizing mechanism” I use…but I’m torn on what to do here…
Before refactoring your functions I would suggest you take a look at your indexes. You would be amazed at how much of a difference well constructed indexes can make. Also, index maintenance will probably require less effort than a “summarizing mechanism”