In a subsequent comment, yes; but in the original comment I responded to, there was nothing about the surrounding context, only (basically) "left % is slow".
Sorry to say, but I stand my ground. I believe it is the left % that is the root issue. As said without further explanation in my initial comment. (it's the same issue on almost every database, and I have never seen it not, being the main culprit, and the solution that never seme to fail is always index)
In a subsequent comment, yes; but in the original comment I responded to, there was nothing about the surrounding context, only (basically) "left % is slow".