1.If needed, strain the yogurt through cheesecloth until it loses about a third of its volume and becomes very thick.
2.Squeeze the grated cucumber firmly in a clean towel to remove as much water as possible, then stir it into the yogurt with the garlic, dill, olive oil, and salt.
3.Cover and refrigerate for at least 1 hour, ideally overnight, so the flavors meld.