node.js else if statement issue, close but no cigar

Question

I have been on this for a good few hours.

I have the below function which reads from a table in my postgres db. It works as expected if there is stored strings in a column.

I can't get the 'else if' statement to work when there is no string in a field. To test this out I have a completely empty column under brand_code and its still executing the 'else' statement.

Now, I know why. There are 3 rows in the table. When I change the else if to === 3, it works as I'd like.

What code do I need to make the 'else if' statement work if the field is empty? (I plan to expand the SELECT statement later).

readCodes: function(callback) {
      var pool = new pg.Pool(config.PG_CONFIG);
      pool.connect(function(err, client, done) {
          if (err) {
              return console.error('Error acquiring client', err.stack);
          }
          client
              .query(
                  'SELECT brand_code FROM public.voucher_codes',
                  function(err, result) {
                    if (err) {
                        console.log(err);
                        callback('');
                      } else if (result.rows.length === 0 ) {
                        console.log(result);
                        callback('');
                      } else {
                          let codes = [];
                          for (let i = 0; i < result.rows.length; i++) {
                              codes.push(result.rows[i]['brand_code']);
                          }
                          callback(codes);
                      };
                  });

      });
    }

}

Really struggled with this all day so any help is appreciated.

I am still learning. Prior to last week, I have never coded so apologies if this is amateur hour.

Answer 1

The problem here is that you are checking if it has returned rows or not, what you need instead is to check in each row if the field is empty

I suggest using underscore for iterating over each row:

_.each(result.rows,function(element, index){
  if(element['brand_code'].length != 0){
     codes.push(element['brand_code'])
  }else{
     console.log('empty field @ results['+index+']')
  }
})

---

CODE :

readCodes: function(callback) {
  var pool = new pg.Pool(config.PG_CONFIG);
  pool.connect(function(err, client, done) {
  if(err){return console.error('Error acquiring client',err.stack);}
  client.query(
    'SELECT brand_code FROM public.voucher_codes',
    function(err, result) {
     if (err){console.log('[!] Error:',err); callback('');} 
     else if(result.rows.length == 0 ){
       console.log('[!] Error:','No rows returned!');
       callback('');
     } else {
       let codes = [];
       _.each(result.rows,function(element, index){
        console.log(element , index)
        if(element['brand_code'].length != 0){
          codes.push(element['brand_code'])
        }else{
          console.log('empty field @ results['+index+']')
        }
       })                        
       callback(codes);
     }
    });
  });
}