domain name system - Do CNAME records overrule A records?

I have several A records like so:

Subdomain             IP Address
example.example.com   198.51.100.0

example.com           203.0.113.0

And a CNAME record that looks like this:

Alias              Destination
www.example.com    example.com

I want to make example.com throw a 301 redirect to www.example.com.

So I'd change the last A Record to:

www.example.com       203.0.113.0

And swap the two URLs in the CNAME record to look like the following:

example.com        www.example.com

Question: Is this change going to make example.example.com resolve to 203.0.113.0 instead of to 198.51.100.0?

Answer

If you have an A record for example.foo.com then no DNS record for any other domain will affect that. So the answer is no.

Other facts to bear in mind:

You can't have a CNAME and an A record for the same fully qualified domain

A CNAME is not he same as a 301 redirect.

A CNAME will return the same ip address as the new domain. Your browser will go to that ip asking for the original domain.
A 301 redirect will cause your browser to do a DNS lookup for the new domain and then go and ask for the new domain.

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