title: HTML Checkbox and Mysql in PHP script
body: <p>I have stored multiple user`s information in a table in mysql. These are supposed to be categorized under 5 tags, A, B, C, D and E. The information is stored in the table as follows:  </p>
  
  <ol>
  <li>maybe all the above mentioned tags are used   </li>
  <li>maybe 'A' is used multiple times, same as B, C, etc.   </li>
  <li>maybe only a few tags are used and other are never used to categorize</li>
  </ol>
  
  <p>I am providing checkbox options for these tags in my html generated by a php script, and when the user checks some or all of the options, it should retrieve the checked tags information from the table and do something. </p>
  
  <p>But in my case, when some tags are checked and those are not stored in the table, I am getting an error (since their is no tag information in the table, obviously). In that case, how should I program, so that even though I checked some tags, and their information is not in the mysql table, the program should ignore them and display the information related to other checked tags. I am not able to write the program in PHP with MySQL queries. It can be a checkbox or a select.</p>
  
  <p>Let me know if the question is unclear, since it is a bit complex to explain here in words.</p>