title: .htaccess redirect non existing pages based on index.php page with wildcard and something after it to index.php
body: <p>Please help, some website is arbitrarily adding dynamic query strings to my home page.</p>
  
  <p>For example my home page is www.mysite.com/index.php and they link to many links like this:</p>
  
  <pre><code>www.mysite.com/index.php?a=something-something-something
  www.mysite.com/index.php?a=something-other
  www.mysite.com/index.php?a=some-other-thing
  </code></pre>
  
  <p>And those links are opening on my site, content of page are the same for every page, just like my original www.mysite.com/index.php</p>
  
  <p>There are few hundreds of that links pointing to my site. So how I can redirect this:</p>
  
  <pre><code>www.mysite.com/index.php?a=something-something-something
  www.mysite.com/index.php?a=something-other
  www.mysite.com/index.php?a=some-other-thing
  ...
  </code></pre>
  
  <p>to</p>
  
  <p><code>www.mysite.com/index.php</code> or just to <code>www.mysite.com/</code></p>
  
  <p>This what I tried so far in my .htaccess file</p>
  
  <pre><code>RedirectMatch 302 ^index.php?a= http://www.www.example-ste.com/
  RewriteRule ^/index.php?a=(.*) http://www.example-ste.com/
  </code></pre>
  
  <p>But still pages are opening on site.</p>
  
  <hr>
  
  <p><strong>Another similar question.</strong></p>
  
  <p>How to redirect pages ending with "<strong>?pagewanted=all</strong>" to the same page but with out that <strong>"?pagewanted=all"</strong></p>
  
  <p>For example I need to redirect page:</p>
  
  <p><strong>www.mysite.com/something-something/something.html?pagewanted=all</strong></p>
  
  <p>to</p>
  
  <p><strong>www.mysite.com/something-something/something.html</strong></p>
  
  <hr>
  
  <p>Hello.</p>
  
  <p>I just noticed something. I needed URL redirection rule which will redirect pages like:</p>
  
  <pre><code>www.mysite.com/index.php?a=something-something-something
  www.mysite.com/index.php?a=something-other
  www.mysite.com/index.php?a=some-other-thing
  </code></pre>
  
  <p>to home page of site, root. And you gave me this code:</p>
  
  <pre><code>RewriteEngine On
  RewriteBase /
  
  #if the query string has an a parameter
  RewriteCond %{QUERY_STRING} (^|&amp;)a= [NC]
  #Redirect and remove query string parameters
  RewriteRule .*  http://www.mysite.com/? [R=301,L]
  </code></pre>
  
  <p>And I must say it works fine, it does that, but I just noticed that it somehow blocks or redirect all links containing <code>?a=</code> for example on some temporary pages I have links like:</p>
  
  <pre><code>i.php?a=something-something-something
  </code></pre>
  
  <p>So, can you adopt code just for pages based on index.php like:</p>
  
  <pre><code>www.mysite.com/index.php?a=something-something-something
  </code></pre>
  
  <p>and not for links with:</p>
  
  <pre><code>i.php?a=something-something-something
  </code></pre>
  
  <p>If I am right it works on all links with "<code>a=</code>" but I need just for "<code>index.php?a=</code>"</p>