title: Concat function is not working - invalid number of arguments
body: <p>I have a table with two columns(Name, Occupation). I want to output the value in a format something like this.</p>
  
  <pre><code>Jane(A) 
  Jenny(D) 
  Julia(A)
  </code></pre>
  
  <p>Hear First one is the name and the value in brackets is the first letter of their occupation.</p>
  
  <p>So far what I have done is</p>
  
  <pre><code>SELECT CONCAT(Name,SUBSTR(Occupation,1,1)) FROM OCCUPATIONS;
  </code></pre>
  
  <p>which output value like this</p>
  
  <pre><code>JaneS 
  JennyS 
  JuliaD
  </code></pre>
  
  <p>to get the required format I tried this</p>
  
  <pre><code>SELECT CONCAT(Name,"(",SUBSTR(Occupation,1,1),")") FROM OCCUPATIONS;
  </code></pre>
  
  <p>then it's throwing an error something like this.</p>
  
  <blockquote>
    <p>SELECT CONCAT(Name,'(',SUBSTR(Occupation,1,1),')') FROM OCCUPATIONS 
    *  ERROR at line 1:  ORA-00909: invalid number of arguments</p>
  </blockquote>
  
  <p>What is the mistake that I have done and what should I do to fix it.</p>