Fix multiple DB login issues

lib/backends/pg-query-runner.js

@@ -1,6 +1,7 @@
 'use strict';
 
 var PSQL = require('cartodb-psql');
+const dbParamsFromReqParams = require('../utils/database-params');
 
 function PgQueryRunner(pgConnection) {
     this.pgConnection = pgConnection;
@@ -22,13 +23,7 @@ PgQueryRunner.prototype.run = function(username, query, callback) {
             return callback(err);
         }
 
-        const psql = new PSQL({
-            user: databaseParams.dbuser,
-            pass: databaseParams.dbpass,
-            host: databaseParams.dbhost,
-            port: databaseParams.dbport,
-            dbname: databaseParams.dbname
-        });
+        const psql = new PSQL(dbParamsFromReqParams(databaseParams));
 
         psql.query(query, function (err, resultSet) {
             resultSet = resultSet || {};