title: How to resolve this error "MySQL Error: 1109 (Unknown table 'table_name' in MULTI DELETE)"?
body: <p>I'm using PHP and MySQL(Server version: 5.5.31-0ubuntu0.12.04.2) for my website when I run the following query it's giving me the above error. I couldn't get any clue behind this error. Can anyone help me in resolving this error and suggesting the changes if any to my existing query? For your reference I'm writing my query below:</p>
  
  <pre><code>DELETE
     ABC.theory_sheet_set,
     ABC.theory_sheet_questions
  FROM
     ABC.theory_sheet_set AS theory_sheet_set,
     OCN.theory_sheet_questions AS theory_sheet_questions
  WHERE
     theory_sheet_set.theory_sheet_set_id = theory_sheet_questions.theory_sheet_set_id
     AND theory_sheet_set.theory_sheet_id=".$theory_sheet_id
  </code></pre>
  
  <p>The error it gives is as follows:</p>
  
  <pre><code>MySQL Error: 1109 (Unknown table 'theory_sheet_set' in MULTI DELETE)
  Session halted.
  </code></pre>
  
  <p>My database name is <strong>ABC</strong>. Actually all the table names are valid and all the tables involved in this query are present there into the database. Can you please help me in resolving this issue? </p>