title: How to find gaps in sequential numbering in mysql?
body: <p>We have a database with a table whose values were imported from another system. There is an auto-increment column, and there are no duplicate values, but there are missing values. For example, running this query:</p>
  
  <pre><code>select count(id) from arrc_vouchers where id between 1 and 100
  </code></pre>
  
  <p>should return 100, but it returns 87 instead. Is there any query I can run that will return the values of the missing numbers? For example, the records may exist for id 1-70 and 83-100, but there are no records with id's of 71-82. I want to return 71, 72, 73, etc.</p>
  
  <p>Is this possible?</p>