title: DELETE whole table except for one row
body: <p>Suppose I have a database with a table which contains 200k+ rows.<br>
  This table has a fixed tuple with id 1800. The rest of the tuples sequence starts at 300k+.<br>
  I have a need to clean this table, delete all records without delete the one register with id 1800. I came up with 3 types of query i could possibly run:  </p>
  
  <pre><code>DELETE FROM table WHERE id &gt; 1800
  DELETE FROM table WHERE id &lt;&gt; 1800
  DELETE FROM table WHERE id NOT IN (1800)
  </code></pre>
  
  <p>I have a feeling that the first one is quicker than the others, but I am not sure, as all of the other data have ids way greater than 1800.</p>
  
  <p>Which one of them is quicker, and why? Also, if there is a quicker way to delete the records excluding the one that cannot be deleted, let me know.</p>