title: REGEXP REPLACE with backslashes in Spark-SQL
body: <p>I have a string containing \s\ keyword. Now, I want to replace it with NULL.</p>
  <pre><code>select string,REGEXP_REPLACE(string,'\\\s\\','') from test
  </code></pre>
  <p>But unable to replace with the above statement in spark sql</p>
  <p>input: \s\help<br>
  output: help</p>
  <p>want to use regexp_replace</p>