Queries involving student groups might be slow when the STUGROUPS table is involved. This is because SERCO developers seem to see no need to have as part of an index the field GROUPID, despite this being a necessary key when finding details which include teachers (TEACHINGROUPS). Creating an index with SetID and GroupID will significantly speed up any such queries (and will have a positive impact on the overall performance of the database).
I'm really posting this for my own future benefit.
It's reasonably useful information for anyone running CMIS. The lack of the index places an un-necessary strain on the database, forcing full table scans where an index scan would do. Without an index, on our database a query was taking a few minutes, with the index, it's almost instant (a second or so). A decent database engine will force transactional consistency on a query (the result will be consistent with the database state at the beginning of the transaction, regardless of any updates which take place during the query). That makes it highly desirable to complete queries quickly.
I marked this as being for future use as I'd previously found this issue but forgotten exactly which table it applied to. I hope to save myself time in the future but it just might benefit others here. Neg rep for that. Whoever you are, you need to get a life.
There are currently 1 users browsing this thread. (0 members and 1 guests)