Using different database for subdomain website

Each site should have its own table_prefix, and you can be selective during export as well as when placing a table_prefix in wp-config.php. Databases are for content and have very little to do with how that content is displayed, however, so I am a bit curious as to how someone else would be interested in having a copy as well as whether you are aware of duplicate content destroying SEO rating.

My curiosity as to how someone else would be interested in having a copy of a site and then the matter of duplicate content destroying SEO rating has to do with the difference between site content (database) and site display (theme). Someone with an existing site would likely want to keep his or her existing content (database) while simply adding a theme from you in order to change how that content is actually displayed.

One of these sites I have completed and my client would like to replace his old website with mine.

Is there a way to grab only website B and use it for the client without any other databases or content from any of the other websites I have created?

To copy/move just one site from one place to another, export the database tables for that site by referencing the table_prefix for that site only as shown in wp-config.php, and then also copy the wp-content folder for that site where its theme and media are stored.

It would be helpful to first know exactly what you mean by this:

One of these sites I have completed and my client would like to replace his old website with mine.

Are you talking about a theme and its settings and a custom plugin or two or are you talking about actual site content? Exactly what does your client want to have replaced?

edit: “Moving WordPress” is the default answer for some situations, but then your client would lose *everything* he already has.
https://www.google.com/search?q=moving+wordpress

on his website’s cPanel…a subdomain and named it ‘newsite’.

So then, right now you can access it by using ‘www.clentdomain.com/newsite/’, yes?

I would leave everything there exactly as it is and use .htaccess to simply redirect his domain to the ‘newsite’ folder.

# BlueHost.com
# .htaccess main domain to subdirectory redirect
# Do not change this line.
RewriteEngine on
# Change example.com to be your main domain.
RewriteCond %{HTTP_HOST} ^(www.)?example.com$
# Change 'subdirectory' to be the directory you will use for your main domain.
RewriteCond %{REQUEST_URI} !^/subdirectory/
# Don't change the following two lines.
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
# Change 'subdirectory' to be the directory you will use for your main domain.
RewriteRule ^(.*)$ /subdirectory/$1
# Change example.com to be your main domain again.
# Change 'subdirectory' to be the directory you will use for your main domain
# followed by / then the main file for your site, index.php, index.html, etc.
RewriteCond %{HTTP_HOST} ^(www.)?example.com$
# use index.php for WordPress
#RewriteRule ^(/)?$ subdirectory/index.html [L]
RewriteRule ^(/)?$ subdirectory/index.php [L]

https://my.bluehost.com/cgi/help/347#redirect

Doing that will remove ‘newsite’ from the access URL without changing anything at all elsewhere.