title: Check string length & ignore whitespace
body: <p>I have some mobile numbers stored in a Oracle DB. I have a stored procedure that carries out some checks around a variety of validations. The stored procedure is launched by a front end Windows application. One basic validation example is ensuring the mobile field is not null.</p>
  
  <p>I'd like to add validation for: check the mobile number is at least 10 characters long, and do NOT count white spaces (leading, after or in the middle) If not, then ignore these mobile numbers.</p>
  
  <p>Example: '188 123 4567' 
  '1881234567'
  ' 1881234 567 '</p>
  
  <p>All thee above numbers should be taken as valid, where as:</p>
  
  <p>'188 123 456'
  '188123456'
  ' 1881234 567 '</p>
  
  <p>Should fail. Can you assist with syntax? I'm still learning PL/SQL.</p>
  
  <p>Here is an extract of the stored procedure I already have in place:</p>
  
  <pre><code>AND NOT EXISTS
  (  SELECT *
       FROM person_a p
     WHERE p.person_id = sa.person_id
    AND p.mobile_ph_no = sa.mobile_ph_no
    AND pu.a_mobile_ph_no IS NOT NULL
  </code></pre>
  
  <p>)
  If the mobile number already stored on the DB is wrong, I just want to ignore it. Not correct it or modify it in any way. Simply if it doesn't meet the criteria, skip over it.</p>