title: replace regex does not work in postgresql
body: <p>I have a table with a column of string. within the string there are single quote which I want to get rid of all single quotes.for example:</p>
  
  <pre><code>"''hey, hey, we're the monkees''"
  </code></pre>
  
  <p>my regex works perfect and select all the values containing single quotes.</p>
  
  <pre><code>select regexp_replace(colName, '%''%', '') from tblName;
  </code></pre>
  
  <p>but it does not update my table when I want to replace this regex with nothing.</p>
  
  <pre><code>UPDATE tblName SET colName = regexp_replace(colName, '%''%', '');
  </code></pre>
  
  <p>I also checked this one </p>
  
  <pre><code>UPDATE tblName SET colName = replace(colName, '%''%', '');
  </code></pre>