title: MYSQL - Concatenate two tables
body: <p>I have two tables as follows:</p>
  
  <pre><code>    TABLE A                    TABLE B
   StuID | actid              FacID | actid
    3       12                  98      17
    5       17                  54      21
  </code></pre>
  
  <p>I want to list the name of everyone, both students and faculty, who participate in activity 17. Is there anyway I can get a result as below:</p>
  
  <pre><code> id  | actid
   98     17
   5      17
  </code></pre>
  
  <p>WITHOUT creating a new table (by just using nesting of expressions or derived relations) ?</p>
  
  <p>A JOIN on the actid would give something like:</p>
  
  <pre><code>StuID  | FacID  | actid
   5        98        17
  </code></pre>
  
  <p>I guess I need a form of concatenation?? </p>