diff --git a/batch/job_canceller.js b/batch/job_canceller.js
index fb41b683..56e1a2e0 100644
--- a/batch/job_canceller.js
+++ b/batch/job_canceller.js
@@ -26,6 +26,10 @@ function doCancel(job_id, userDatabaseMetadata, callback) {
             return callback(err);
         }
 
+        if (!pid) {
+            return callback();
+        }
+
         doCancelQuery(pg, pid, function (err, isCancelled) {
             if (err) {
                 return callback(err);
@@ -35,7 +39,7 @@ function doCancel(job_id, userDatabaseMetadata, callback) {
                 return callback(new Error('Query has not been cancelled'));
             }
 
-            callback(null);
+            callback();
         });
     });
 }
@@ -49,7 +53,8 @@ function getQueryPID(pg, job_id, callback) {
         }
 
         if (!result.rows[0] || !result.rows[0].pid) {
-            return callback(new Error('Query is not running currently'));
+            // query is not running actually, but we have to callback w/o error to cancel the job anyway.
+            return callback();
         }
 
         callback(null, result.rows[0].pid);
diff --git a/batch/job_service.js b/batch/job_service.js
index 99ad458c..ea397461 100644
--- a/batch/job_service.js
+++ b/batch/job_service.js
@@ -36,19 +36,19 @@ JobService.prototype.list = function (user, callback) {
         }
 
         var jobList = dataList.map(function (data) {
-            var job;
+                var job;
 
-            try {
-                job = JobFactory.create(data);
-            } catch (err) {
-                return debug(err);
-            }
+                try {
+                    job = JobFactory.create(data);
+                } catch (err) {
+                    return debug(err);
+                }
 
-            return job;
-        })
-        .filter(function (job) {
-            return job !== undefined;
-        });
+                return job;
+            })
+            .filter(function (job) {
+                return job !== undefined;
+            });
 
         callback(null, jobList);
     });