title: How to get Filed name (Column Name) in couchbase if no result found using N1QL query?
body: <p>I'm writing query to find an user information in Couchbase,I'm getting result as empty array but i want fields with empty result, I was tried couple of time but i won't get the fields the result which are having empty value. How to get the header fields?</p>
  
  <p>My Query is</p>
  
  <pre><code>SELECT C.firstName AS `First Name`,
  C.surName `Last Name`,
  U.auditDetail.createTime AS `Date/Time of the Registration`
  C.contactDetails.`email`.`value` AS `Email Address`,
  C.contactDetails.`phone`.`value` AS ‘Phone Number`,
  C.sex `Gender`,
  C.dob AS `Data of Birth`,
  ag.id AS `Referral Code`,
  C.addressDetails.`office_new`.`zipcode` AS ‘Postal Code`,
  C.addressDetails.`office_new.`city` AS `City`
  FROM data C
  UNNEST C.activeGroups AS ag
  JOIN data_PH U ON U.loginld=C.contactDetails.`email`.`value`
  WHERE U.type_='user'
  AND C.type_= ‘customer`
  </code></pre>
  
  <p><strong>Result:</strong></p>
  
  <pre><code>{
    "results": []
  }
  </code></pre>