Perhaps unsurprisingly that sounds about exactly the same for Canada.
Bans are not necessary, you just need to make them harder to get a hold of. Also regulation such as making clips/magazines larger than 5 rounds/bullets illegal also makes such events more difficult. Canada also has a high gun/population ratio, however almost all fall into the shotgun or hunting rifle variety. Handguns are rare and regulated (literally) to the gun range.
You can never totally prevent this sort of thing, however making guns harder to get would certainly reduce it, and regulating what kinds of arms you can get could limit the severity of it. In the US where you can probably trip over guns, it is just too easy. When it is hard, you really have to plan and deliberate and follow through over a lengthy period, when it is easy, you go nuts or are mad and grab your nearest 8 guns and 200 rounds and go to town in the next 10 minutes.
About the only thing I would say about Canada in the same vein that needs some improvement, is that while there are mental health services and medication availability, Canada does have a homeless mental health issue, which I see every day. We really need to do more there in that regard.