title: Get text after second occurrence of a specific character
body: <p>I have a column with data like this:</p>
  
  <pre><code>firstNameLetter_surname_numericCode
  </code></pre>
  
  <p>For example:</p>
  
  <pre><code>m_johnson_1234
  </code></pre>
  
  <p>I need to extract the numeric code. I've tried with SUBSTRING function but I just get:</p>
  
  <pre><code>surname_numericCode
  </code></pre>
  
  <p>This is the code I've used:</p>
  
  <pre><code>SET number = substring(t2.code, charindex('_', t2.code, 2) + 1, len(t2.code))  
  </code></pre>
  
  <p>How can I get just the numeric code?</p>