Data base, custom field

Hello,

I have a question about the custom field we can create in back end.

For example, I have two different profile type : "Profile 1" and "Profile 2"

In each one this profile type, I create a custom field : "City where you are born"

1- In the database of my website, the answer would be stocked in the same column ?
2- If I want to make a search on the website, if I use this custom field, would it search in Profile 1 and Profile 2 ?

Thanks a lot for your help,

Edouard