title: MySQL search with multiple category id
body: <p>I got a talbe like this</p>
  
  <pre><code>category_table
  
  cat_id   |   cat_name
  ---------+--------------
  1        |  cat 1'
  ---------+--------------
  2        |  cat 2
  ---------+--------------
  3        |  cat 3
  ---------+--------------
  4        |  cat 4
  ---------+--------------
  5        |  cat 5
  </code></pre>
  
  <p>Another table called item table as follows</p>
  
  <pre><code>item_table
  
  item_id   |   item_name    |  cat_id
  ----------+----------------+-----------
  1         |  name of item  |  2
  2         |  name of item  |  1
  3         |  name of item  |  2
  4         |  name of item  |  3
  5         |  name of item  |  2
  6         |  name of item  |  4
  </code></pre>
  
  <p>I have got the following query for select in item_table</p>
  
  <pre><code>SELECT * FROM item_table WHERE cat_id=2
  </code></pre>
  
  <p>I got a category id array like this</p>
  
  <pre><code>$cats=array("2","3","3");
  </code></pre>
  
  <p>My question is how to perform a "multiple category" search using the above mentioned array ? Means I want select all items with category id 2,3,4.</p>