I had it before I joined this gardening site 10 years ago. I don't know exactly how long but kept it in a large container and pruned it. It was about four feet tall and the same width.
The roots would be more vulnerable to the freezing temps in a container. It likely would be better when planted in ground.
Olive (Olea europaea 'Arbequina') PlantFiles says it doesn't like to be as cold as it got this February. I don't like to get that cold either.
Gosh I hate to think about starting another one now that I know how long it took to get to that size.