Can you tell me now to select mild flavored onions when shopping?

We often end up with onions which are way too strong flavored, but occasionally we get mild ones by accident. When shopping for onions, Is there a way to identify mild flavored ones?|||So called 'sweet' or mild onions are usually identified by their shape which is slightly flattened rather than being round.|||buy sweet onions or vidalia onions. Leeks have a mild onoin flavor too.|||There are a lot of different varieties to choose from. Walla Walla Sweet are quite mild and grown in my home state. They look like a yellow onion and it's easy to mistake the two for each other. Vidalia and Spanish mild are also good. Yellow onions are a little milder than white onions and I think red is somewhere between the two. The mildest in that family is the leek, which looks like an overgrown spring/green onion.