We're using Moodle 2.4.1
MSSQL issues are like playing whack-a-mole. There's always more of them-- it even causes a number of unit tests to fail. Oh well, we're living with it.
I filed the tracker report before posting here as https://tracker.moodle.org/browse/MDL-37788 -- I just thought I'd get quicker response here to the suggested workaround-- it comes up quite a bit.
The affected tables in this case are mdl_scale, and mdl_grade_outcomes.
Generally in the past I've posted the error, and locally done a cast, until the problem is fixed properly then I patch our instance.
I'm happy to change core code, but not so happy to change the core schema.
Of course we have a development instance-- that's where I tested that changing the schema would solve the immediate import outcomes problem-- it's the "I'll just wait here quitely and jump out at you later" problems I'm want to avoid.
Obviously there is not agreement on this point; I'll eschew altering the schema, and wait for a proper fix.