Using htaccess to redirect the page but keep the U

Question

I have a dynamically part static and part dynamic url I wish to redirect to another page but keep part of the URL the same (domain).

My structure will be as follows:

www.domaina.com/query(folder)/?123,456,789

To redirect to

 www.domainb.com/query(folder)/?123,456,789

But I wish to keep the URL in the address bar reading as domaina.com not domainb.com.

The sites are on different servers and htacces rules will differ from site to site (some may be static sites in the root and some maybe wordpress etc) and will sometimes be on different servers.

Thanks

Answer 1

<frameset rows="100%">
<frameset cols="100%">
<frame src="http://www.domain.com/page-i-want-to-display" frameborder="0" scrolling="yes">
</frameset>
</frameset>

Answer 2

Look into iFrames instead of doing this with htaccess code.

Edit|Update: Use iframes and not frameset. frameset is not supported in HTML5. See this w3schools tutorial page. Adding an iframe is very simple so keep everything very simple - http://www.w3schools.com/tags/tag_iframe.asp