title: regular expression where the value must contain Letters, blank space and numbers
body: <p>How to get a regular expression to define if the value contain Letters, blank space and numbers.</p>
  
  <p>NOTE: The value must contain letters, numbers and blank space.</p>
  
  <p>eg.</p>
  
  <pre><code>Maalderijstraat 45            Valid
  Tronestraat                   Not Valid
  Tronesttart45                 Not Valid
  123456                        Not Valid
  </code></pre>
  
  <p>I' using this query:</p>
  
  <pre><code>select a.street
  from clients a 
  where REGEXP_LIKE (a.street,'^[a-zA-Z0-9]*$')
  </code></pre>