Added a link to an overview in the mysqli section of the manual.

The Overview is also of relevance to the MySQL extension.


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@275568 c90b9560-bf6c-de11-be94-00142212c4b1

reference/mysql/book.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<!-- $Revision: 1.2 $ -->
+<!-- $Revision: 1.3 $ -->
 <!-- Purpose: database.vendors -->
 <!-- Membership: bundled, external -->
  
@@ -18,6 +18,10 @@
    Documentation for MySQL can be found at <link
    xlink:href="&url.mysql.docs;">&url.mysql.docs;</link>.
   </para>
+  <para>
+   For an overview of MySQL database connectivity terms 
+   and products see <xref linkend="mysqli.overview"/>.
+  </para> 
  </preface>
  <!-- }}} -->